No, you won't be able to max out GW2 at any resolution with that card, but it will be playable at low and medium settings and still look good.
What? Excuse me? I have the GTX 550 ti 2GB VRAM version with a 1GHz OC and I can play on high at 1680x1050. Oh and I'm running a second monitor as well, my idle temps are 50C and my load temps are ~60C.
Now, I just launched GW2 and played around with my settings:
Guild Wars 2 is not a very demanding game, the 550ti can and will play it on 1920x1080 with decent high settings with ease. Sure it can't max it out but for you to say that it can't at any resolution is insulting. And it looks very good on high(and plays very good on high as well).