APPROXIMATE PURCHASE DATE: ASAP, dependant on price BUDGET: genuinely, as cheap as possible, dependant on longevity though. Ideally < £150.
USAGE: gaming (everything from old Bullfrog titles to new 2011 releases)
CURRENT GPU AND POWER SUPPLY: Integrated Intel i3-540 GPU, soon-to-be-replaced Antec SP500P PSU
OTHER RELEVANT SYSTEM SPECS: see forum sig below
PREFERRED WEBSITE(S) FOR PARTS: Scan, ebuyer, Overclockers... but basically, whoever's cheapest.
PARTS PREFERENCES: NVIDIA (compatibility with The Last Remnant and others), most likely a GTX460 and I'm guessing a 1GB is worth the extra money but I want your views on that
OVERCLOCKING: Maybe - new to it, considering a factory OC GPU SLI OR CROSSFIRE: No (no mobo support)
MONITOR RESOLUTION: 1680x1050
I've been considering the Asus ENGTX460 DirectCU (possibly TOP, the factory OC model since I've yet to try an OC myself) and also potentially the EVGA GTX460 SuperClocked, which is significantly cheaper than the OCd Asus. I notice the Asus has better cooling, but don't really know if that is enough for it to beat the EVGA. Additionally, I'm not really sure which way the scales are tipping with regard to 1GB over 768MB and the additional cost it would incur.
With the GTX460's, custom cooling is a plus, but not a necessity. The stock models generally run cool and quiet. Either of those cards would be great, and I can recommend whichever one has the best ratio of factory overclock to price. The 1Gb models are the best, but at your resolution, if you want to pay less for a 768 Mb model, you won't miss much if anything.
I would personally say get teh 1GB card as you state newer games and its those that will be swapping big lumps of textures about for which more memory is definatly going to be better.
The 560 is due out on the 25th i think it was last i heard so i guess its worth a wait.
Basically what matto17secs said about just getting the best price/perf ratio. Post some links if you like and we can run a Pro's and cons sesion for you.