Main change in the XX cen. The Republic of China and the Cultural Revolution
On 12 February 1912, with the collapse of the Qing Dinasty (1644-1921) 2,000 years of nearly continuous imperial rule came to an end. Afterward China endured decades of disruption and civil war, becoming first a republic and then a communist nation.  Under Mao, both Buddhism and Daoism were harshly suppressed.  Temples  were destroyed, land confiscated and priests and nuns were forced back into lay life.  Daoism endured particularly harsh measures as it was regarded as a deviant superstition that was harmful to the people.
In the 20th century, simplified versions of some of the techniques of the Daoist masters became everyday practices to promote good health and longevity — for example, physical exercises such as Qigong.  Elements of Daoism remain within traditional Chinese medicine, arts and in popular entertainment.
Recently, there have been some efforts to revive the practice of Daoist religion.  In 1956, the Chinese Daoist Association was formed, and received official approval in 1957.  It was disbanded during the Cultural Revolution under Mao, but reestablished in 1980.  The headquarters of the Association are at the White Cloud Temple (see p. 8), that now serves as a training center for all the daoist sects, and is able to grant ordinations in any of the traditions.
As China was reopened to the west in the latter part of the 20th century, the interest of tourists, scholars, and overseas Chinese in traditional religion motivated the Chinese government to allow the rebuilding or restoration of a number of Taoist temples and monasteries, and thousands have now been reopened, most of them belonging to the Way of Celestial Masters (see sec. 5) or to the Complete Perfection (see sec. 8)tradition.  
Complete Perfection adepts take vows of celibacy, Celestial Masters adepts are often married, and often reside at home. 

Acknowledged Authority: The Chinese Daoist Association
The Chinese Daoist Association (CDA) founded in April 1957, is the main association of Daoism in the People's Republic of China.  Dozens of regional and local Daoist associations are included in this overarching group, which is encouraged by the government to be a bridge between Chinese Daoists and the government, to encourage a patriotic merger between Daoism and government initiatives. The group also disseminates information on traditional Daoist topics. The CDA advocates the recompensation of losses inflicted on Daoism by the Cultural Revolution.
Daoist practitioners in China are required to register with the CTA in order to be granted recognition and official protection. The CDA exercises control over religious doctrine and personnel, and dictates the proper interpretation of Taoist doctrine. It also encourages Daoist practitioners to support the Communist Party and the state.

Main rites: Everyday contemporary practices
It is difficult to write about lay activity in Daoism, because generally speaking only Daoshi (Daoist priests) are understood to be "Daoists."  Daily involvement with Daoism on the part of the laity is not ritualized in any particular way.
There is one area in which the Daoshi are still actively engaged with the laity.  The Daoshi  serve as consultants to those members of the community who have personal problems or illness. Often the Daoishi will write a talismanic symbol that embodies the energy of his vital power to be transferred to his "client." 
The Daoshi will also sometimes prescribe herbal medicines, perform acupuncture, or do an astrological reading, always in conjunction with a ritual.
Unlike laypersons, the Daoshi have a rigorous life of daily practice.  While in training, a great deal of time will be spent learning every aspect of ritual performance. In order to maintain and nourish the vital energies, they perform several self-cultivating practices like gymnastic or breath-control exercises, special diets, meditation, along with the keeping of a strict moral behavior. Visualization practices are common in order to establishing harmony with the celestial realms and with the Dao

Main Rites: The Jao
The term Jiao means "offering" or "sacrifice." It refers, in the present day, to the large-scale Daoist ceremonies on beahalf of the community, usually a blessing for the community or to ensure a prosperous renewing of the life-cycle.
These rituals may involve many villages, and occur every three, five, or twelve years.  They can be extraordinarily expensive, and are paid for by the community.  Aside from the rituals themselves, there will also be plays, processions, military parades, and communal meals. Daoist rituals are colorful, filled with music, incense, and stylized movements.  Much of Chinese drama is influenced by Daoist ritual.
The presentation of a written memorial is the heart of the ritual, conducted by Daoshi and their assistants.  The memorial is a petition to the gods, written in literary language, stating the name and purpose of the ritual, its date and location, the names and addresses of the participants, and a vow — that is, a request and a pledge on behalf of all the participants.
Afterward the master burns the memorial and scatters the ashes. In breaking down the ritual space, all talismans, writs, and other markers of the ritual space are burned. Afterward there is a communal banquet.

Source Analysis
Source n° 1
The People's Republic of China was established as officially atheist, having viewed religion as emblematic of feudalism and foreign colonialism, and maintained separation of state and the church. This changed during the Cultural Revolution, in 1966 and 1967. The Cultural Revolution led to a policy of elimination of religions; a massive number of places of worship were destroyed. In this poster A Red Guard at work is smashing, among others, a statue of Buddha, a crucifix, Confucian and Daoist classic books. These religions and their temple, monasteries and properties were considered old, bourgeois or decadent.
The Chinese words state: "Scatter the old world, build a new world".

Source n° 2
Voice comment:
Hello, my names is James Miller and I am in Hong Kong to witness the ultimate day of the twelve day Daoist ritual: Luo Tian Da Jiao (Great Ritual Offerings to the All-Embracing Heaven).
Here the people are getting ready for the beginning of the ceremony this sunny afternoon in Hong Kong. Having assembled, these large temporary altars has been erected behind the actual building of the temple. The priests  and all the people that are attending the ceremony are getting ready for the ritual.
There are three priest that are dressing white and they're about the get their ritual vestments, and in doing so they transform themselves in to three gods. the Sanqing (Three Pure Ones, see p.5), the three primal energies of the universe. In the Daodejing,  the principal, classical philosophical book of Daoism there is the phrase: "The Dao become one, the one become two, the two became three and the three became the ten thousand things".
These three daoist priest are the personification of these three primal energies of the universe, and on behalf of all the people they will be offering petitions to the gods for the well-being of the state, they celebrate the tenth year of reunification of Hong Kong to the mainland, China, and they will pray for the stability and security of the land, for the flourishing of people's lives.
The Luo Tian Da Jiao is a ancient ritual, going back to the Tang Dynasty (618-906), over thousand years ago, and it is one of the most elaborated and extensive of Daoist ritual. This in particular is ongoing for eleven days, and it will finish tomorrow, November 24th, 2007. The ritual site here is set up as a square and there is a small altars at each of the four corners of the square and in the back, signifying the five directions, meaning the whole of the universe. To the back of the altars there is another stages as well where all the gods are arrayed in statue form. Here the three priest are individually making prayers and chanting according to the scriptures that you can see set in front of the altars . Two accolades come and adjust the capes of the priests so that when they stand up they won't trip over themselves.
As you can see here Daoism has a very rich material culture not only as the music - you can't see the musician but they are in the back of the picture here, there is an extensive live orchestra that accompanies chanting. You can see also the vestments, very richly, decorated and all the various ritual implements, altars, and the movements that the priest is making here. In this next phases of the ritual each of the three priests are going to be taking these small incense holders, they’re going to be lighting this incense making this ritual movements, bowing down to the floor, moving the incense in certain proscribe direction. You can see the very precise way the priest moves the incense in the incense holder and making this movements using the whole of his body.
Basic principles of Daoist rituals says that the priest that perform this ritual movement  will also be directing the flow of energy inside their bodies. This is a kind of external, visual representation of something that is also taking place internally, deep inside their own meditation, that they are also performing at this particular time. There you can see the priest handling off the incense and new incense being put in the holder. There is a constant procession of incense that is brought to the priest and taking away from him and you can see the handing over taking place here. Actually this ritual last much longer than in this video. It could last half an hour and many stick of incense will be used here and taken back to the back of the temple.
In the next part of the ritual we're going to see all of the priest and the various assistants  moving away from the main altar that is on the top of this ritual ground and make a procession to visit all of the altars that have been erected for this ceremony. You can see here an enormous space with all of the many assistants to the ritual.
Processing in the background you can see the three priest dressing red. They are making particular ritual hand gestures and they're carrying with them incense and they're about to make a procession to the altars you can see in the background here. They will be making petitions at that particular altar. And you can see not just the priest performing with all the people, but there are people come to take photographs. This is very much a spectacular ritual performance and it is being filmed for television.  It was broadcast in the news when I was in Hong Kong.
Here the priest stopped in front of the altars making petitions at this particular altar.
This procession is a symbolic gathering up of the whole world into the offerings that have been made to the principal altars at the top.
Of course one of the main principles of Daoism is the idea of balance between Yin and Yang and here it is express symbolically in the participation of these women, and also in the fact that they are in a number equal of that of men, but they are divided by sexes here. At the end of the women procession there is the beginning of the sequence of man who are going back to the main altar.
Finally let's see these shorts of the people processing. We can just see principles of daoism symbolized by the colors: black and white, Yin and Yang; and also yellow, the imperial color signifying the splendor and august nature of this ritual uniting the people with the highest spheres, establishing the bonds between Heaven, Earth and Humanity, bringing all together into a numinous harmony. This is the ultimate goal of this ritual and it is express symbolically even in the color that we see here.

Source n° 2
Qigong (Qi Exercises) describes a group of practices highly popular in China (albeit strictly controlled by government), in Taiwan and increasingly well known the West. As a modern system of healing, it goes back to the 1940s. Qigong involve slow, gentle body movements, breathing exercises, self-massages, and the mental circulation of Qi . It aims to provide a free flow of Qi energy, help in healing, and in general create a sense of greater well-being and openess of spirit. The most obvious and direct forerunner of Qigong is Chinese gymnastics, known as Daoyin (see p.4). Qigong successfully combines techniques that go back to both medical and Daoist sources.  It is practiced both in the medical community and actively pursued among Daoist followers.
However, From a strict Daoist point of view, insofar Qiqong aims only to improve one's psycho-phisical wellness, it is considered just a preliminary step, a valuable  tool to nourishing life, but still secondary to the religious attunement with the Dao.
As for the (maybe more famous) Taiji quan (Ultimate Boxing), it is part of the so-called Chinese internal martial arts which feature health exercise, meditation and self defense techniques. Historically speaking, Taiji quan is a non-religious martial arts. Although its philosophy is framed by the Yin and Yang and Five Agents theory, its connection with Daoism seems to be a modern construct. However, it cannot be denied that many mainland Chinese Daoists practice Taiji quan, applying certain Daoist principles to transform Taiji quan into a “Daoist practice", de-emphasizing the martial applications and highlighting the  meditative and health-preserving  dimensions.

Intercultural, interdisciplinary information
-For Taiji quan, see above
- Concerning the popular (mis-)conception of Daoism, see:
http://www.daoistcenter.org/daoism3.html
http://www.daoistcenter.org/daoist3.html
http://www.daoistcenter.org/Daoism_Misconceptions.pdf