pretty good, if you wanna save 100 bucks you can go with an i5-2500k maybe get the cheaper version mother board save another 50 dollars so there's 150-200 bucks you can use to upgrade to a gtx 580 if you wanted or keep the money.
if money isn't an issue, that build look's pretty good to me, it's similar to the one im building I am using an 2500k with the 129.99 motherboard. with the os included tax's and shipping it online just break's the 1,500 mark.
but if you plan on eventually getting 2 video cards id stick with the Pro version that you have selected.
solid rig as is; if you will be playing any modern games at 1920x1080/1200 or above, the jump to the GTX580 is a big jump, but, worth the extra $200 due to the extra memory/framebuffer size (If only a $100 jump if you re-use an old DVD ROM, I'd try hard to 'go for it'....sell some plasma twice in one week, and you are there!)
you will virtually see no difference ingame with an i5 2500k verse's the i7 2600k maybe 2-5 more frames if that, and with a gtx 580 or even the 570 that isn't gonna make any difference for gameplay. and if you do get the 129.99 asus p8p67 motherboard and the i5-2500k and get the gtx 580, that psu you picked out should be good for a single gtx 580
for a single GPU the 580 is about as good as it gets right now for actually speed, if your not into heavy gaming you can stay with the 570 and if you are really going budget go for a 6950 or if you are just a casual gamer, you play most games on high but not very high a 6850 or even a 6870 might fit the bill.
Sorry I should mention you can get video cards that take up one pci-e slot that are more powerful then the gtx 580 but these are dual gpu cards, look up radeon 5970 as an example.