latha - 4:55 am on Dec 5, 2012 (gmt 0)
Facebook Contests work really well. Facebook has rules which says no Facebook property can be used to launch or run a contest - means the facebook page, the comments.
You need to use a third party app or create a contest on the facebook tab.
I have seen many companies using the facebook page and running contests (not the tab which is allowed).
I am not sure when they will get into trouble. I am using an app for my clients.