Can't tell whether the mobo is a good deal or the right one because I couldn't (easily) figure out which Asus mobo it is. Asus is a good company, but until the mobo model is known can't say much else.
Same is true of the vid card - there are very good GTX 580s available for nearly $100 less, so you should compare specs and decide if +$100 is worth it. Too much trouble for me to look and compare.
Your monitor is a 27" 1920x1080 screen, a combo I personally prefer. (Had to go to the Newegg site to get that pretty important spec lol.) provides decent resolution for gaming and larger text size for, eg, looking at Tom's without shifting from the monitor's optimal setting. But you may be thinking your getting a 2560 resolution scree, which you personally may prefer.