It only matters if you need to use more PCIe lanes than the Z68 chipset has available.
Unfortunately, it does not appear that Intel has upped the number of PCIe lanes available with next year's upcoming 7-series chipsets, so waiting would be of no benefit either.
Core i7-2600K @4.1GHz, GIGABYTE GA-Z68XP-UD5, 4x4GB G.Skill RipJaws PC1866
Corsair 650D case, Seasonic X750 Gold PSU
WD `Raptor 600GB boot, WD Caviar Black 1TB data, NEC 7200 DVDRW
XFX 6970 2GB, Hauppauge HVR-1800, X-Fi Titanium, Dell 2407WFP