As the New York Times detailed yesterday the Chinese government is activating legislation that may give problems to the possible Microsoft Yahoo purchase. The new Chinese law would "give Chinese regulators authority to examine foreign mergers when they involve acquisitions of Chinese companies or foreign businesses investing in Chinese companies' operations. Beijing could also consider national security issues, according to a report by the official news agency Xinhua.," NYT reported.
Given that China now has the world's most internet users and all three of the major search engines are involved in the country there could be impact for all of them.
Apart from the Alibaba ownership that Yahoo has, Google also has invested money in Baidu. These economic influences on the engine could impact censorship decisions and other actions.