I run on MAC and I was wondering.. what AA level is the best? x2, x4, x8, x16?..
Anti-Aliasing
It doesn't matter much whether you're running on Mac OS X or Windows or Linux. As Curious-Mewkat says, what matters most is your hardware (and the drivers, but you have little control over that). You're going to trade graphics quality for graphics speed. The same thing happens when you choose among Low, Medium, and High graphics quality.
Basically, try out various settings, and see how much your computer can take. If you find your game stuttering or being unresponsive, so that your play is hindered, then turn your settings down. Otherwise, play on the best settings your computer can handle.
The higher the AA, the better looking game.
Have't really noticed any difference in SK, though.
I keep mine at x8, play around with the graphics settings (not just AA) and then see what's bestfor your personal preference.
Depends on how well your Mac can handle it. The higher the AA level, the greater the performance cost, so try to experiment and put it at a level that is suitable for your mac to run it.
For best performance, put it at the minimum level.