Is it WoW or my computer that is messed up?

Before the 4.2 patch my computer ran WoW completely fine. Now after 4.2, the game crashes all the time, especially in Orgrimmar. Now I can't even load one of my characters without it crashing. It's starting to annoy me because I just bought more game time and I might not be able to use that time if the game keeps crashing. I know I have a lot of space on my computer to allow the new Patch and anymore data that needs to be updated. but my computer is all up to date with everything. WoW is just bugging out and crashing and I've tried repairing it and it didn't work.