Haswell is expected to come out next year around the second half...or it was quarter. Doesn't matter because that's already rather late. Haswell is also a new socket (LGA1150) so there's no point in future proofing because Intel is basically switching sockets every single time to milk some more money out of you, whether they get the money or not. Performance jumps will be rather small so they'll probably seem insignificant under regular use. I obviously won't be using integrated graphics so that doesn't matter to me, unless I think about getting a notebook (which I'm not as of now).
Haswell has the possibility of performing worse than Ivy Bridge at the cost of efficiency. Haswell is reverting back to a flat transistor without the fins in their "3D transistor" that's currently being used in Ivy Bridge, so the performance might drop, even if they can fit more transistors onto the die. So I don't expect much from Haswell. If Haswell does well and I feel the need to upgrade, I might have some spare cash or borrow some from my parents and then sell my motherboard and processor (and maybe heatsink) and buy one for LGA1150. Only Haswell-EP supports DDR4 anyways (I think EP is their server and workstation parts, so basically, Xeon).