It is widely reported that Facebook has obtained a license to operate in China and most likely, the operation will be done through a joint venture with Chinese internet giant Baidu (NASDAQ:BIDU), as reports said Baidu CEO Robin Li visited Facebook last February.

Most likely, Baidu should have 50 percent or above stake in the joint venture, and the service will likely be isolated from Facebook's global site for regulatory concerns.

We view Facebook entering China as a positive headline for Baidu shares, Susquehanna Financial analyst Ming Zhao wrote in a note to clients.

Zhao said, like Google (NASDAQ; GOOG), Baidu has been unable to bear any fruits in social media. Baidu may have a chance to achieve a meaningful presence, with the help of the Facebook brand name.

Whether this initiative will be a meaningful earnings driver depends on if Facebook could become a gateway for accessing the Internet, which could increase search queries, as well as brand ad+game revenues for Baidu, the analyst said.

The analyst also downplays Facebook's potential in China. In China, the successes at Tencent QZone, Renren.com, and Kaixin001.com will make Facebook's performance more uncertain. Without the same help from game apps as in U.S., Facebook is merely a product that helps users to know what friends are doing, versus Weibo to know what the world and friends are doing.

User behavior would not be as sticky as Weibo, in our view, the analyst said.

As a result, Facebook needs to develop from scratch in China and may take several years to taste success.

It also takes time to build an ecosystem, though arguably a lot of game apps on Facebook are developed by Chinese studios. Facebook will be under strict regulation, which is less of a concern because Baidu will do the filtering.

The analyst also gave a more optimistic picture on Chinese microblogging site Sina Weibo and said the Facebook's entry in China will only have a minimal impact on the site.

We view Weibo as a better product in terms of connecting people and receiving information. The competition from Facebook is late, and will be very limited, in our view, Zhao said.

Sina Weibo already has over 100 million users, a figure possibly reaching 200 million by the end of this year.

The core question we have is, rather - Will Sina continue to consider BIDU as a partner in terms of powering search on its portal and Weibo?, the analyst wrote.

That partnership sounds a bit shaky now, with Baidu's partnership with Facebook. If Baidu loses the opportunity to be Weibo partner, it is rather negative for the search giant, Zhao said.

In addition, the news will trigger a lot of questions on Renren.com's upcoming IPO. Renren.com already faces competitions from Weibo in users' time. When the real Facebook is coming, the copycat of Facebook in China certainly will have more challenges.