If the card is not mentioned somewhere in the big list of supported/unsupported cards just ask around on some gaming forums (not amazon since hardly any gamers come here). And you can always see if you can run SC2 well. Games should not to be different in performance demanding eh... thingy.
I've been looking around the forums and they seem to think it will run fine which is good news! personally i think it will struggle a bit and the fan will be on the whole time, but i guess we'll know on tuseday!
i have a 2011 macbook pro top of the line with i7 processor and 1gb dedicated graphics and i runned the beta just fine with all stats very high.. and yes the fan its allways making noise.. buy something to refresh your mac
The open beta ran fine on my machine, which sports an i5 with HD3000. I wasn't concerned about fancy graphics though. The performance of the HD3000 improves dramatically with dual channel access to RAM - or even better, dedicated memory. As far as I am aware, Apple puts RAM into both available slots, and they should support dual channel access.
Don't bother with a 13". They only have integrated graphics. A decent 15" with a dedicated graphics card should be able to run it fine for example my MBP 15" with 6750M runs it just fine on med-high settings at native res