I'm trying to decide between a BenQ XL2720T with Invidia 3D kit that I would buy after or just sticking with 2D and getting at least a 29" or 30" screen if not bigger (LG EA93 and yes not as good for FPS most likely but would be cool).
Currently running a 660ti 3gb overclocked card in a new build with a i5 3770k chip but the card itself will also be upgraded eventually to a 780 or 690.
If I stick with 2D then I might replace the 660ti with an AMD card. (Anybody interested in a semi-new 660ti lol)
Also aesthetics are a factor which is why I was looking at the EA93 monitor as it matches my build (White Storm Stryker, White Level 10M mouse, White Q701 headphones etc) and setup in appearance as well as offering multiple display options without bezels.
I do not like 3D but up to you if you do get a bigger monitor get one with a high resolution 2560 x 1600 might cost a bit but if you are going to get a 7** gpu or two it would look sweet crysis 3 maxed out sweet. If not then your 660ti will last you at 1080p for some time. As for moving over to AMD for the GPU I always use nvida so I really cant help you sorry.
If it is 3D capable you do not have to us it in 3D mode. As for the LG it is a very nice monitor I saw a review on youtube on it the guy got a couple of GTX Titans though it will work well with 770's or 780's. Tested a few games. Real sweet looking but AC3 did not support the larger screen size so right now that might be a small down side to this monitor. If that bugs you try one of these. Try and get low response time <6m/s and a decent contrast ration 100K:1 minimum is what I would go for.