Does lower resolution look better on smaller screens?
Maybe down at the 11" level, but you won't be able to get a big enough GPU such a small laptop.
Ideally, you'd get a laptop with a 1920x1080 screen, but then it'll need a GPU that's twice as powerful (and needs twice the cooling), so the whole laptop will need to get bigger, and the weight starts to stretch the definition of "laptop"...
Desktop PCs don't have all these compromises, but if you need a laptop you just have to be aware that it won't be perfect
Thanks for the advice. I played on 13 inches before, it was decent. I'm not quite sure why you think it ruins the game
It's all subjective. I can say from experience that the chat font used in Diablo 3 (at least the beta), can be hard to read at resolutions lower than 1600x900. It's too small for the amount of pixels. I think this is something Blizzard will have to address eventually, but it's something anyone thinking about playing the game at 1366x768 should be aware of.