Luo Zhenyu at a promotional event for his new book Logical Thinking 2 in Shijiazhuang, Hebei province.

Le has nearly 41 million followers on micro blog Sina Weibo, each time he posts, he receives thousands of comments, forwards and likes.

When Le posted about his new book, he prompted a huge reaction online.

Luo Zhenyu, host of the online social-issues talk show, Luoji Siwei (Logical Thinking), did not bother holding a media conference to promote his new book, instead he simply reached out to the talk show's more than 1 million WeChat followers.

Ahead of the publication of his new book in October last year, Luo announced the news through WeChat, a popular mobile messaging platform. When the book was on the market, he launched a series of online promotional events using social media, including Sina Weibo and WeChat, asking his followers to show others and comment on his book.

His followers were so supportive that one of the events made the top 10 topics on Sina Weibo, reaching an even wider audience.

It is common for fans to help publishers and publicity firms to organize promotional events for celebrities' books, both online and off it. Many fans promote the books through word of mouth, technically called viral marketing.

When Lin told the media that he would publish an autobiography, his fans suggested he used more photographs taken in his youth, and some fans e-mailed him soft copies of photos they have kept all these years. The photos taken by fans are an even more complete record of Lin's career than his own collection, according to a Beijing Youth Daily report.

Liu Jiehui, vice-president of Beijing MediaTime Books, also one of the largest private publishing companies in China, says that since social media brings celebrities and fans much closer than traditional communication channels, it is easier for publishers to rely on celebrities' influence on fans to promote books, yet the quality of the books also matters if they are to be successfully sold on the market.