Looks good. PSU is about right for your needs -- you don't want it operating at 100% all the time. Case is personal preference. Note one issue with the ram. If you choose to get the overkill aircooling NH-D14, your ram won't be compatible with it -- its too tall. Go for some Vengeance low profile ram if you can.
Motherboard looks solid, looks like you are getting a hell of a deal there, also with your i5 as well.
GPU is pretty solid, although I much prefer this cooler, and its not much more if you manage to get the rebate. The cooling is outstanding and quiet, and the card is clocked higher as well to boot.
is twice as better as a 7770, and not all too much more infact. I don't like to push up your build costs too much, but it was wrong of me to suggest a $150 7770, my mistake for that.
This card can easily handle 1680x1050.
i5 3570k - 180
Asrock Z77 Pro4 -- 50
8GB Low Profile Vengeance -- 39.99
Rosewill Challenger -- 49.99
CX430/CX500 -- the CX 500 is currently the same price as a CX430 with rebates, however you are not guaranteed to get the rebate. Something you might want to consider. -- 34.99
Oh sorry, my email is really dodgy sometimes. 500W is more than enough, 430 should be enough as well, but you are on the fringe of it (You don't want your PSU running at 100% all the time).
The issue with having a 1GB card means you are restricted with what settings you pick. I know for a fact that BF3 uses 1.5 GB of vram maxed out at 1080p. The issue is, is say you had a 560TI 1GB SLI'd, it could easily run BF3 at max, however, the vram would cause constraints, meaning you'd have to lower the settings, which actually gets rid of the point of buying a second card. There are some cards which have the horsepower, but not the fuel, if you know what I mean.
Sorry about not responding, T.H seems to sometimes send me emails far too late, I only got your reply today.