Windows 7: Can my graphics card handle it?

yeah that's a decent laptop saw a video on youtube of someone playing crysis at decent settings with little lag with that laptop, it will probably run diablo 3 better then the other laptop you suggested around 1280x720 with the built in quad core in the lappy along with the HD 6520G built in. Should be playable at medium-high with decent resolution at around 30fps is my best estimate. So yes you should be able to play diablo 3 with that laptop.

A desktop will always be cheaper than a laptop of equivalent performance, even if you include the accessories and computer desk :P

That's pretty cheap for a 17" laptop. Hmm, according to the regularly updated master graphics card list, it uses a really low end card. Like, tail end of class 3. A 15" screen laptop would be cheaper than that 17" one, and the price difference could go into a better graphics card. Are there any other models on offer where you're looking?