If you are not in any hurry I would say wait. Reasons :
1. Ivy-bridge is on the rise.
2. PCI-e 3.0 is only now being adopted seriously. Native support for it in Ivy-bridge is worth waitng for. This will also drop pricing on these insanely priced boards.
3. Same goes for USB3, native support in Ivy-bridge will give true USB3 performance as seen in AMD APU compared to third party controllers.
4. AMD and Nvidia (hopefully sooner rather than later, if only to drive down AMD prices) HD7xxx and GTX7xx series GPU's are being release.
So yes, I think give it a wait. Although Graphics card future proving is not easy. I have found thats its best to get a just better than necessary card at the right price and then upgrade it alone as the need arises.
BUT why the I7? What will you be using this PC for?