I'd recommend the GTX 460 over the GTX 465.
The 460 runs cooler, uses less power, and is competitive speed wise with the 465 in a lot of games. Plus, it's cheaper.
The GTX 460 tends to run around $199 (768MB) to $250 (1GB memory).
I'd say a 5770, GTX460, or even a 5830 are all around a similar price, and all good choices.