The final setup looks pretty awesome! My only suggestions would be to consider looking at a cpl of things. Look at the Asus P6X58D-E. Great board with sata 3 and usb3. If interested, ocing with this board is amazingly simple.
I like Mushkin memory, but as I said, these are something to look at, great products. Any lifetime warranty memory is a pretty good choice. The only other thing with memory is to either get a 12gb kit, or 6 2gb sticks.
Video Editing is somewhat more demanding when it comes to memory. Try 1 6gb kit, if it seems to top out, add another.
Definitely want modular psus. Seasonic. Corsair, XFX, and a few others are pretty good choices, with my preference being Corsair, like you.
While I generally like to have good leeway available when it comes to supply and demand, but a good 650 watt unit should be plenty for that system.
Looks like he's got a good system coming! It's nice to help out a friend, and of course you get to build it and tweak it. A goooood stress test.
Enjoy the build, as your friend will I'm sure!!!

