In general, Mesa and Wine still have problems. I have been filing bugs for the issues I find and the developers are looking into it, but it's not a high priority at the moment.
You will probably need to play around with the OffscreenRenderingMode option in Wine and possibly also turn of GLSL to get supported titles running correctly.
I have no idea about WoW, but with current git master I'm at least able to play Portal on my G45