Gigabyte GTX 275 896 MB
Gigabyte EX-58 UD3R (MOBO)
Intel i7 920 at stock speed of 2.6 (Have just installed Noctua on it and will be playing with getting it to 3.5 but for arguments sake lets keep the stock speed in mind)
6GB Cosair dominator DDR3 1600
Termaltake Toughpower 750w
Currently sit at around 27-50 FPS but not on full settings, I would like to run on full if possible although top AA and derivatives are not imperative.
Upgrading to play Guild Wars 2 but also play most current gen games like BF3, MP3 etc
You should be able to run GW2 on full settings with a newer graphics card.
I have a very similar setup (my i7 920 is already overclocked to 3.6, any i use a GTX 285), and i get between 25 and 70 FPS with everything set to "high" + FXAA. I'm using "fullscreen windowed" mode (1920x1200) because that is more comfortable for switching to my 2nd screen, if I use normal fullscreen 1920x1200 I get a few FPS more.
Guild Wars 2 is not that graphically intense, BF3 (and other FPS) are much more demanding.