The big hype about the new Maxwell GPUs is more hype than product, in my honest and humble opinion. What I mean by that is the architecture of the GPUs is changing, the GPU cores are only having slight changes. That means that the new GPUs will be more efficient, use less power, and produce less heat. They won't necessarily be way faster than the current breed of Nvidia GPUs. An 860 isn't gonna be waaaay faster than a 760. Of course the new GPUs are going to be pricier, so if I were you, I'd stick with the more than adequate 760 for now, and later get one of the new Maxwells, or whatever comes after that. Maybe even cross over into AMD if they produce some interesting tech.
Hope this helps!