The most recent changes to Facebook's Promotion Guidelines has created confusion around running a competition using Facebook, but here is the 'dummies guide' spelling out the terms for you.
Tag: iFrame page
iFrames – What You Need To Know
iFrames are definitely here to stay - for the time being anyway! Although they are not as readily available for the 'non-coder' Fan Page owner to access like fbml code was, iFrames certainly offers a lot more than fbml could ever do - and hence the reason Facebook switched.