That would mean tweaking the bios a little too see that work. Newegg listed the board itself as 677 while Asus clearly points out 667/533. As far as how the Geil memory would run that would be chancing it depending on it's own backward capability there.
While OCZ, Corsair, Kingston, and Crucial are all known brands I can't say good or bad on Patriot since that's a relatively new brand there in comparison to the others. The one brand seen at Gigabyte is Kingtson there with Corsair seen at Asus. For a gaming machine you will want to look at preformance memory like the Corsair xms series or Kingston HyperX if you plan on ocing anyways. Without ocing take your pick.
I have OCz DD2-667 in a GA-965P-S3, it took a BIOS update (board shipped with the F2 BIOS = crappy, no memory support) but it was relatively painless to get set up.
I don't see any reason the Patriot RAM wouldn't work.
edit: Patriot may be a new brand but they are basically PDP, a memory maker for the last 20 years or so.
I'm not surprised to hear that Patriot is being made by an established manufacturer there. That was probably a marketing move with the new name being used. Their home page is found at http://www.pdpsys.com/ The Patriot home page is found at another site which notes PDP at the bottom of the page seen at http://www.patriotmem.com/
The corsair is out of stock. The patriot may not OC quite as far as the XMS2, but on the other hand it might, you've got 0.3V on the XMS2 that's already used up unless you drop the timings.
Yes, latency is measured in clock cycles. When you have more clocks to work with the latency goes down. If you had some PC3200 @ 3-4-4-8 and some PC5400 @ 3-4-4-8 the amount of time lost on the 5400 is less even though the latency timings are the same.