Blizzard has already changed its stance on race changes from an unpopular position announced earlier today. Blizzard will now be allowing you to get a paid race change to take advantage of the new race/class combinations when patch 4.0.3a drops tomorrow.
We know this is confusing, but this the real deal. Blizzard will let you change to something as awesome as a tauren paladin starting tomorrow.
The full blue statement is as follows:
Note, you will not be able to race change to a goblin or worgen until after Cataclysm hits the live servers on Dec. 7 at 12:00 a.m. PST.