I am going in for a new system and have got these specs ready. If you could provide feedback, that would be great, since I want to ensure the system turns out to be something good for recent video games running at fairly good settings. Any things that I should consider changing that would make too much of a difference to the price but will increase performance? Is the 580W PSU enough do you think?

Are you going to buy all those parts, or do you already have some/all of the parts on that list ?
If you haven't bought the parts yet, then please let us know your budget.

The list is okay, I would pick some different parts than you have had.
This depends on what I mentioned earlier, if you already own some of the stuff on the list and its dumb to go buy something ells now.

The PSU is okay if you keep the system the way it is and do not upgrade. ( wouldn't suggest SLI )
Personally I would suggest something like 620W or above.

I would also suggest a 600w+   psu  for stability and future upgrades.  I would suggest going with a Corsair psu.

Your psu is fine for your specs but like everyone else I would recommended getting at least 600w for future upgrades, especially since you have a mobo that supports SLI. Also try and get a psu with a single 12V rail. I know Corsair psu's have that disign.