The 660 Ti is hardly close to the reference 7950s anymore (let alone non-reference models), it doesn't consume much less power at all, it overclocks like crap in comparison, and you can notice the difference at any resolution thanks to MSAA.
Furthermore, AMD has been much better about driver optimization this generation. They went from behind Nvidia to in front of Nvidia purely through improving driver optimization greater than Nvidia did.
Some of the best 7950s are $300 too and come with almost $200 in free games. 660 Ti better value? No, it is not. It's not even close.