I use the I7 920 still, it is a solid CPU. I don't have it overclocked either. I just upgraded my graphics card to the MSI geforce 570 GTX Twin frozr II. I run with 6 gigs of ram, I would upgrade to the Corsair Vengeance 12 gig kit but for now 6 gigs is doing me well.
I got the graphics card for 250 from newegg.com. If you are looking for a newer card, but not the newest and want to spend between 200-250 on your card. The 570's are solid cards. Though at that point I would just go 570, 580, 590 depending on what you are willing to spend. But if you want a 580 or 590 I would just get a Geforce 670 for 407$.
EVGA geforce 490. I recommend this only if you don't care how much you want to spend. This is the newest GPU and, if you can spend the 400 its worth it. If you're on a budget I would not get this card.
http://www.newegg.com/Product/Product.aspx?Item=N82E16814130787
MSI geforce 570 GTX twin frozer II card. This was on sale when I got it for 250 I think overall with shipping and handling I ended up paying 279 for it. This has a custom fan by MSI that keeps it about 20 degrees C cooler. It is a solid card and, I am very happy with it.
http://www.newegg.com/Product/Product.aspx?Item=N82E16814127682&Tpk=geforce%20570%20gtx%20twin%20frozr
Just to touch on something Sarosan said. I am also a visual nut, I hate knowing I am not seeing the best my computer could put out. But if you can wait, I would wait and get a 6 series NVIDIA card (or the equivalent ATI card. As far as a whole new system, I would just wait. I have the same CPU, same amount of ram, granted my motherboard is probably faster, not sure, its the EVGA X58 Classified board.
Even with my old card, Raedeon 450 HD it ran GW2 pretty nicely, just not at max settings. With the new card I was running smooth at max settings. That is something to consider.