Think that from here to a few months you will probably get a Z77 motherboard, an Ivy, one of the new graphics cards like the 7850, and who knows even an SSD that supposedly will drop in price this year. So don't speculate too much because things change, the PCIe 3.0 is not going to be a difference with a 2.0 graphics card and maybe not even with a mid-range 3.0, but it's about having room for maneuver, especially for the future.
You're right, besides I'm going to build the computer in the summer and from here to there things can change a lot thanks for the advice.
Regards.