It's Merriam-Webster's Word of the Year for 2007!

1. w00t (interjection)
expressing joy (it could be after a triumph, or for no reason at all); similar in use to the word "yay"
w00t!

Merriam-Webster Online
rebgirl420 Reviewed by rebgirl420 on . "WOOT" may soon be in the dictionary! It's Merriam-Webster's Word of the Year for 2007! 1. w00t (interjection) expressing joy (it could be after a triumph, or for no reason at all); similar in use to the word "yay" w00t! Merriam-Webster Online Rating: 5