American Idol will air tonight on Fox (8/7 c); Voting begins immediately after the show.
According to the Idol release, fans will be allowed to vote up to 50 times per Facebook account and only Facebook users from the US, Puerto Rico and the US Virgin Islands are eligible to vote online.
American Idol/Facebook is a natural fit. The Idol page already has 4.7 million likes and a very active wall. The show attracts a demographic that is very active on Facebook and naturally generates discussion and debate over its performances.
This should be a pretty successful cross-channel promotion for the show.