i would imagine wow would be entirely too taxing for a macbook.
just tried civilization IV.
actually told me as it started that the machine did not meet minimum requirements.
i started it anyway, mae sure all the graphics options were turned down (he game did this for the most part on its own. also turned off the movies, music, and voices. started a "tiny" world, went through the startup options and when i finally was dropped into the world map i heard a buzzing coming from the right speaker.
cmd+tabbing out of the game stopped the buzzing.
going back into the game restarted he buzzing as well. so i went into the sound options and turned everything off except for interface sounds - as i clicked off the ambient sounds the buzzing stopped.
i just did a few turns and while i miss the little animations from when i played this on my old 17" HP laptop, it seemed playable. my cpu also seemed to stay around 150-155, though the fan ran constantly.