Anyone who thought that MMO Champ would have free reign posting alpha stuff obviously weren't around for Cataclysm alpha when exactly same thing happened. On this sort of stuff MMO Champ has been the nice lapdog of Blizzard for a very long while now. Last time they had p. much free reign on posting alpha stuff was back during WotLK alpha when this site was the number 1 site to go for all the leaks and probably large reason for it's initial rush of popularity.
Modern gaming apologist: I once tasted diarrhea so shit is fine.
"People who alter or destroy works of art and our cultural heritage for profit or as an excercise of power, are barbarians" - George Lucas 1988
They can toss the DMCA at you quite easily. They are copyrighted assets. You only hear about it with music but anything digital is covered. Not to mention there's probably a NDA associated with the Alpha as well.
I should add even if the Alpha is able to be downloaded, unless you specifically are authorized to do so Blizzard has the right to take legal action. Will they? Probably not.