Those sites were around during the last election, and they were used by students and volunteers to mobilize campaign efforts. But this year will likely see a lot more use of networking sites by the campaigns themselves.
In Maryland, the two Democratic primary candidates have launched official Facebook profiles, in an effort to reach students (Facebook is geared toward students; its members are supposed to have a ".edu" email address).
But like wiki files, these entries can be faked, as well. Current Maryland Gov. Robert Ehrlich, who's running for re-election, also has a Facebook profile. But Ehrlich's profile--- which lists his interests such as "getting terrible haircuts" and "raising more taxes in 16 months than Democrats did in 16 years"---is a phoney. It was created by the president of the Maryland Federation of College Democrats.