480 is around 25% slower at Anisotropic filtering, so a GTX 560 ti would have slightly clearer textures and blur objects further away to give the illusion of distance. But, this isn't as important as AA - AA is the most noticeable and jaggedy's just look unnatural. In terms of AA, the 480 is 28% better. It's really down to personal preference - whether you prefer AA or AF. Whichever you think improves the game quality the best is going to be the better card.
Of course these figures are just theoretical, but they are pretty accurate.
The gtx 560 ti and the Gtx 480 are around the same price, but I would say get a good cooler for the GTX 480 as they are noisy and hot - with a new cooler you will have the capacity to OC a little if you so desire.
With a good cooler, I don't see any reason against the 480 being able to compete or being slightly better than a 570. (AF is only 5% more on the 570 which is practically nothing unless you have a massive resolution monitor)
Conclusion: Get a gtx 480 with a good cooler and you will have a beast of a card.[/quotemsg
Thanks! The GTX 480 it is.