The sad case is, my 13" MBP 2009 plays Starcraft 2 perfectly, but at low settings, it stays rock solid at around 30fps in even the highest combat times. No dips in framerate (~300 units, large battles.) I've already seen that the 11.6" MBA buries my performance in running Starcraft 2. Must be the graphics card. I would imagine particularly the 11.6" Ultimate would play medium settings and still match my MBP in high capacity battles. Still regardless. A 2009 MBP can fully play SC2, but has to use lower settings. The 11.6" MBA runs this game faster than my MBP.
If you want to test out truly what settings you should have in SC2, simply download one of the competition replays from the Starcraft 2 replay site. They show some good skilled matches, with tons of great micro used, mouse-click indicators in real-time, and large scale battles that generally go up to around 300 units or so. That's been around the most I've seen used in a match due to resource and building vs. Time limits on how many units each player can support.
