Still open to changes all around, especially on the monitor (3x 23s are cheaper and give better response and more pixels, will one 590 support it? I have plans to get another 590 in the future, perhaps also upgrading to an X79 based chipset.
Monitors - I've got a x3 setup with the samsung 750d, and it is the best monitor ive ever used. http://www.newegg.com/Product/Product.aspx?Item=N82E168...
you lose three inches, but its 120hz and 2ms. Once you've experienced 120hz, you cant go back. It makes games rock solid and absurdly realistic (mostly fps) and browsing and such is waaaay nicer too. plus, its beautiful and has 3d if you care about that (works with all games, kinda cool). It's not IPS but its colors are only a hair behind - i can only tell a difference when i have it side by side with a good IPS. the only downsides are its a glossy screen and its hard to mount if you wanted to do that.
lastly, id say go with an OCZ vertex3 SSD - it's cheaper and better. Its got synchronous NAND and some of the best benchmarks.
Also There are better fully modular power supplies available now. The SeaSonic X-SERIES X-1050 is the same price and a better PSU in my opinion. The Corsair HX 1050 is a good PSU but it's getting old now.