Get a gtx680m in your laptop it is pretty powerful also the next generation laptop graphics won't prove much of a improvement on the current generation. So you are better off with a 680. If you want more graphics power get dual hd7970 or dual GTX680 in it.
As Xttony said. The 680m will keep you happy for a few years; as long as you understand how much the laptop will cost with a top of the range card such as this
...and appreciate that you'll get far, far more for the same money with a desktop (I know it's for school but you know what I mean).