Need Help Choosing New GPU

Hey Guys,

I've tried my luck with the GPU comparisons here but I can't seem to find any comaprison that will show me the difference between my current GTX 295 and some of the newer GeForce 500 series GPUs. I want to upgrade badly because I want DX11. System specs are as follows:

i7 920 D0 Stepping w/ Cooler Master V8 CPU cooler & Diamond thermal paste
6GB DDR3 1600 Mushkin RAM
2 x 1TB 7200 WD Black FALS1000 Hard Drives in RAID 0
EVGA X58 LE Mobo
Thermaltake 1000W PSU
Thermaltake Spedo Advance Case

I built this computer with the intention of soon buying a monitor worthy of the GPU but life happened and it didn't work out that way. As it stands now I have a 1366x768 Samsung LCD TV hooked up to it. I'm not really a resolution whore like some people, I just want somewhere between 720p and 1080p to run smoothly at max settings as long as it's DX11 and will last at least a year doing so until I buy the next iteration. I was looking at a GTX 560 Ti but don't know if that will be comparable to the GTX 295 I bought a couple years ago. Should I go with a 570 to be safe?

Also, I have been out of the loop for quite some time on the AMD side of things and have no idea what compares with the Nvidia chips insofar as performance is concerned. Honestly I'm leaning towards AMD anyways as my previous experience with Nvidia has left a bad taste in my mouth with regards to driver issues, loud noises, etc with my 295. Any and all input you have is welcome. Thanks!