The entries will be judged by a panel of developers, and if you win, you'll not only receive one of Epic Weapons' Frostmourne Replicas, but a guaranteed slot in the upcoming beta for WoTLK. 2nd and 3rd place runners up will also receive a slot in the beta.
It should be noted that the contest is currently being announced on the European site, and the rules state that the contest is open only to residents of France, Belgium, the United Kingdom, Luxemburg, Germany, Austria, Sweden, Finland, Denmark, Norway, the Netherlands, Spain, or Ireland. There doesn't appear to be any word yet on whether we'll get an American version of the contest, but here's hoping we see that soon. It seems likely that Blizzard had to create two seperate contests because of legal requirements, and is still working on getting the US version up.here.
[Thanks to all our tipsters for sending this in!]