One or two months out of the World of Warcraft with my account currently frozen, I received e-mail regarding 7 days free game time in Cataclysm. I am already upgraded to Cataclysm and I don't know if only those people who are enrolled in the expansion are the only ones who received the offer.
You can claim game time by going to:
https://www.worldofwarcraft.com/account/claim-promotion.html?promoId=SEVEN_DAYS_PROMOTION
If you aren't aware of what Cataclysm is or the features in the expansion are, then click here to find out more.
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