We were hoping to hear some kind of announcement regarding the status of the Wrath of the Lich King Beta during Blizzard's WWI. There was little information to be had at the event, however, they have just announced that they are now taking applications for the beta.
If you head over to the official WoW site and log into your account, you'll find a handy link for the beta opt-in. If you're feeling particularly lazy, you can just click here and it will take you to the right place.
We still have no word on when they will begin sending out beta keys, however, I would imagine that we'll be hearing more in the coming weeks (if not sooner). We do know that the selection process will be totally random, so you've got just as much of a chance as anyone else.