Why do you think there's such a huge difference between SC2 and D3? If you compare the videos from both games that have been released (the gameplay movies and such) you won't notice that much of a difference. I'd reckon both games will have sorta same specs in the end. Obviously this is just me guessing.9400M should be more than enough for starcraft 2. Heck the gma x3100 might run it on lower settings.
Diablo 3 is a different story. Won't run on ANY intel integrated chips. I'm pretty sure the 9400M would work, since it can run fallout 3, but I don't know about highest settings.