OSX is using OpenGL . Thats not the problem , Warcraft III runs pretty good on my mac mini . no problem , but hten it lags when i run it on top of my hac.Its mainly because of the emulation , even such an old game , it lags. so pretty much you're better off running warcraft III on windows then on an intel mac / but if you're talking about ppc imacs its fine

i have dota'ed on my mac mini ...i have no what-so-ever problems