[quote name='TheRock88']So do you need to get the email for it to work? Or can you just download the client and it'll recognize you already own SC2?[/QUOTE]
This is the exact wording of the e-mail:
"Thanks a lot for being an early supporter of StarCraft II. The community is off to a great start, with over four million players worldwide and I'm pleased to report that the rumors of the death of real-time-strategy gaming have been greatly exaggerated.
As a thank you for your early support, I've flagged your Battle.net account to receive a free, downloadable copy of World of Warcraft. This is the full version of World of Warcraft that we sell in store and includes a 30-day subscription. Just follow the instructions below to activate it, download the game, and start playing. Again, it's totally free."
So I guess the question is what is there window for "early" supporters? Depending on when you activated SC2 on your account the free WoW should be there.