TV GUIDE is allowing the members of Facebook to vote on which series will be featured on the cover of the December 12 issue of the magazine. GAME OF THRONES is vying for the honor with nine other series.

http://www.facebook.com/TVGuideMagazine?sk=app_262168817154382

If I understand correctly, to vote you first have to "Like" TV GUIDE. Then you get to cast a ballot.