Blizzard survey email - is this a scam?

I got this email. I clicked the link, it looked legit, had the same log in as the wow forums, but at the end of the survey they want my personal information, account name and secret question. Is this legit or a scam?

Greetings!

You are receiving this email to notify you that you have been chosen to take our free Blizzard Entertainment Game Survey, when you are done, you will recieve 10 free days of game time, which, after a verification period of 5 days, will automatically be added to your account.

The survey is meant to rate and critique Activision Blizzard games so we know what to do for future games releases.
The survey is 100% free of charge, and we highly suggest you take it.

You will need to take the survey at http://www.worldofwarcraft.com/blizzardsurvey/id=123151 to finish your registration for your free 10 days of game time.

Thank you for your time and attention to this matter as well as your continued interest in World of Warcraft.

Regards,

Account Administration Team
Blizzard Entertainment Inc
P.O Box 18979, Irvine,CA 92623