Build recommendations

[ZJ94]

Getting ready to drop the hammer on a new build, but since this is only the second PC I'll have put to together I'd appreciate feedback from all you pros out there. I'll be using the PC mostly to run MMOs (specifically Guild Wars 2) at 1920x1080 and hope to run on high settings with this build.

I plan on reusing the case, OS, HD, & DVD from my previous build. To the best of my knowledge, no issues there.
Original HD: Seagate Barracuda 7200.10 ST3250310AS 250GB 7200 RPM 8MB Cache SATA 3.0Gb/s 3.5"
Original DVD: LITE-ON 20X DVD±R DVD Burner Black SATA Model iHAS120-04

Considered reusing my PSU as well, but not sure if its up to running this build or not. Thoughts?
Original PSU: Antec earthwatts EA500 500W Continuous Power ATX12V v2.2 80 PLUS Certified Active PFC
http://www.newegg.com/Product/Product.aspx?Item=N82E16817371007

New parts:

Mobo
ASRock Z68 Extreme3 Gen3 LGA 1155 Intel Z68 HDMI SATA 6Gb/s USB 3.0 ATX Intel Motherboard
http://www.newegg.com/Product/Product.aspx?Item=N82E16813157271
$121.99

CPU
Intel Core i5-2500K Sandy Bridge 3.3GHz (3.7GHz Turbo Boost) LGA 1155 95W Quad-Core Desktop Processor Intel HD Graphics 3000 BX80623I52500K
http://www.newegg.com/Product/Product.aspx?Item=N82E16819115072
$219.99

PSU
OCZ ModXStream Pro 700W Modular High Performance Power Supply compatible with Intel Sandybridge Core i3 i5 i7
http://www.newegg.com/Product/Product.aspx?Item=N82E16817341018
$89.99

GPU
EVGA SuperClocked 01G-P3-1563-AR GeForce GTX 560 Ti (Fermi) 1GB 256-bit GDDR5 PCI Express 2.0 x16 HDCP Ready SLI
http://www.newegg.com/Product/Product.aspx?Item=N82E16814130610
$249.99

RAM
G.SKILL Ripjaws Series 8GB (2 x 4GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Desktop Memory Model F3-12800CL9D-8GBRL
http://www.newegg.com/Product/Product.aspx?Item=N82E16820231314
$46.99

Looking at about $740.00 shipped with the new PSU. I'd be willing to throw a bit more $$$ at it, but only for appreciable performance gains. Toyed around with upgrading to a 2GB 560Ti, but not sure the extra VRAM is necessary at 1920x1080.

Anything I've missed or could change to improve the build?

 

[ubercake]

Everything in your 'new parts' list looks solid. I would definitely go with the new PSU because you'll be pushing it if you OC the processor at all.

If you're going to throw more money at the video card, go for a 570 ( ie http://www.newegg.com/Product/Product.aspx?Item=N82E16814130620 @$299) rather than a 560 with additional RAM.

I would recommend a 60GB+ SSD to run your OS and drivers to gain some speed.