I just got this email over the weekend, and think its a cool recruitment method! We help Blizzard get additional subscribers and we get free game time! A win-win for all involved. I mean really, who doesn't know someone they would like to corrupt, err, indoctrinate, err, INVITE into the game.

Check your inbox for the Recruit-A-Friend e-mail!
We are in the process of sending out e-mails to every U.S. subscriber to World of Warcraft. Each of these e-mails contains one 10-Day Guest Pass Key you can use to recruit a friend into the game. If your friend then becomes a paying subscriber to World of Warcraft, then you will receive a FREE 30-Day Credit to your World of Warcraft account. So be sure to check your inbox over the next couple of days for your Recruit-A-Friend e-mail!