The power of online social networking was demonstrated by the tens of thousands who gathered in Shanghai at the weekend to pay their respects to the people who died in last Monday's blaze.

The event at Jiaozhou Road was launched on microblogs and information spread rapidly on the Internet, especially on social networking sites such as Kaixin001.com.

According to a survey by Shanghai Daily and Touchmedia, of 110,000 people traveling in taxis in Shanghai, Beijing, Guangzhou and Shenzhen, 57 percent of interviewees use social networking sites or microblogs for more than half an hour a day, and 18 percent for more than three hours.

Microblogging is the most popular form. Almost 60 percent of the interviewees said they publish information on microblogs, communicating with friends, following celebrities, expressing their opinions, sharing jokes and conducting online marketing, said the survey.

"Many breaking events are first released or arouse public attention through microblogs," said Xie Yungeng, a researcher of Shanghai Development Strategy Research Center and professor at Shanghai Jiao Tong University.

Sites such as Kaixin001.com are becoming increasingly popular. Some 44 percent of interviewees use them daily.