Even as social networking sites like Facebook start to brag about their revenue from job recruitment advertising, the latest edition of Time (August 20), quotes the following stats:

12% of employers admit to consulting social networking sites like Facebook for help with their hiring process.

63% of those employers declined to hire an applicant because of what they found - including faked qualifications.

Time doesn't say what country or planet those numbers apply to, but the only thing that would surprise me is if it was as little as 12% doing Facebook snooping. First thing I'd do if hiring someone (after the requisite Google search) would be to rat around LinkedIn, Facebook and so on.