Guild Experience - 4.0.3/a?

Been trying to find an answer on this one, but it's a tough one to compose a specific search term for.

I'm not positive there's ever been a specific answer, but does anyone know specifically when guild experience/advancement/achivements get "turned on"? Is it going to be in 4.0.3, or not until Dec. 7th with the actual release of Cataclysm proper?