Yep, I have left Planeshift myself. Downloaded latest version and normal wilds where before I had almost no problems were just a series of pictures. Same like the the Fortress in version before. After relight I just had a huuuge lag and what for? I didnt notice better graphic. *shroughs* The PS version I enjoyed the most was 0.11 anyway.
So now Im running WoW without a problem. Im not going to buy new Mac just becauce PS cant run on this one when everything else does.

*EDIT
I couldnt help myself and after this post I recently did another test... Lag is indeed too much to bear. As surplus when I change anything at PS setup, PS crashes after trying to load the world. Tested with two separated PS folders, all the same. Tried to add no grass maps, no good. In short what I wrote up in this post is right.