> Will the Chinese administration really be able to suppress freedom of opinion on the internet, anonymous or not?

It depends on whether the Chinese people will start to care enough about politics that they can set up a BBS that doesn't get shut down. For example, if all the college students (the most active group) started using Freenet, or set up a Tor type of thing that let them connect to some BBS hosted in America, then an anti-government movement could get started again.

China has been shutting down big political BBSes for five years now, eventually someone will get tired of it and make a route around the censorship.