How do I enter? Just keep your account active.
Who is eligible? US Citizens who don't live in states like New York and Florida where it is prohibited. There are other people who are ineligible, so please check the sweepstakes rules page.
How do I know if I've won? They'll choose your character with the most played time and list the character's name and server on the WoW main site. Then they will notify you by email within the next 5 days -- so make sure the email that you have listed in your account info is current.
Will Voice Chat be enabled and working on my server by the time I'm eligible to win a headset? The first week ends October 6, so we all should have had Voice Chat enabled on our servers by that time. Theoretically.