The previous comment is absolute tripe and has been Scientifically proven many many many times. If you look in to it, BBC has been testing with 300 (three hundred) FPS broadcasting for their sports scenes because in rapid action sports scenes the current broadcasting framerates just aren’t cutting it on large display areas.
If you seriously believe you can see NO difference between 30 FPS and 60 FPS (simple test) then you, sir, are either a genetic anomaly or you just haven’t tested. Don’t believe the hype, test things for yourself.
As for Mac client tweaks – I have been tweaking with mine and will report back if I find any specific options which help a lot. Although if you’re playing on a mac laptop, you may want to install smcFanControl (http://www.macupdate.com/app/mac/23049/smcfancontrol) and crank the fans up to max before you start playing. Fighting high temperatures back down is difficult, keeping the hardware cool in the first place means your GPU never gets hot enough to start dropping frames and underclocking in the first place.
Hope this helps!