Do GTX 580, 570, 480, 470 and other 4xx provide the same CUDA features?

Are they only difference in term of # of core and performance but provide the same CUDA features?

Yes.

For all intents and purposes, yes. 570/580 and 470/480 are sm_20 cards, while the other 4xx cards are sm_21. As far as I can remember, this is just a difference in instruction scheduling within a kernel. There should be no user-visible differences between the two.