I am pretty much going to be buying a laptop for this game. A desktop is outta the question. I was interested in an Alienware Machine. Processor Intel® Core™ i5-430M 2.26GHz (2.53GHz Turbo Mode, 3M cache) Memory 6GB DDR3 at 1066MHz Video Card 1GB4 ATI Radeon™ Mobility HD 5730 With Starcraft 2 Around the Corner, I need to start saving up. I am willing to boost the processor to a Intel® Core™ i7-820QM Quad Core Processor 1.73GHz (3.06GHz Turbo Mode, 8MB Cache) the video card to 1GB ATI Radeon™ Mobility HD 5850 and the memory to 8GB Dual Channel DDR3 at 1333MHz – 2 x 4096MB I figure if i could run it on ultra with the first settings i have up here, why spend an arm and a leg?
You need to look for a big bag of money. I think you will be better of buying a decent desktop now, and buying an 'ok' laptop in like 5 years time. Then even the cheapest will run SC2 on ultra like a charm.
Get as much RAM and GPU as you can afford, the rest is less critical. Try to get a quad core CPU, but a dual core will do fine.
MSI GX640. I just bought this laptop, hoping to play games (especially SC2) on it, and it plays it with ease. I have all graphics on Ultra, Audio set to high quality, on native resolution, online even in 4v4 with massive amounts of units.. no lag whatsoever. For the price ($1100), it can't be beat. I highly recommend it Btw it has a Core i5-430m, ATI Radeon 5850 HD, and 4GB Ram. The processor is in no way a bottleneck. It is very powerful.