If you must go the intel route even though your main goal is to build a fast gaming machine.....
The P5N32-SLI is a better board than that G1975X. But also be aware that the latter is crossfire and the former is SLI.
From the reviews I have read, that G1975X has a bad layout design. Should you ever go to use two graphics cards, there is no room for the remaining PCI cards. In other words you wouldn't be able to fit in a sound card (etc).
The P5N32-SLI also has two x16 slots when in SLI mode (as opposed to the G1975X, which has two x8 slots in crossfire mode). It is known to be a little "buggy" but asus is putting out bios fixes. Most reviews say it is an amazing high end motherboard.