TT (yeah, taboo...apologies) shows 660 is essentially 90% the speed of a 7870 for all intents and purposes (with AA), or half-way between a 7870 and 7850. Pretty much what the specs (equal to 1120 radeon shaders, tdp between 7850/7870) imply. I suppose if you look at it from a somewhat delusional and cherry-picked perspective, it is similar to 7870.
Still think it should be a $220-230 (if 7870 250), then 200 (if 230) card. It probably will be once the launch fervor is over, 7870 gets a cut, and have their prices settle. 7870 is looking better and better as it gets cheaper...clearly Pitcairn is the better-designed budget chip. It seems AMD is staking claim to the 'these chips don't need 2x6-pin but it allows us to make them cheaper and offer better value with overclocking' philosophy the past couple generations. I think that will pay off vs 660 as the overclocking prowess gets over some tangible walls at 1080p 660 won't be able to match, if only barely.
There is an argument to be made for the design though; less rops (which are not needed on 7800 but part of the setup engine structure which is groups of 16) should somewhat help offset the greater shader units in Pitcairn, so it should clock reasonably well with similar power (both will use ~150w overclocked even though 7870 has another power connector). It seems at the end of the day AMD just makes a more compact design to do the same task...probably down to the slower, be it wider, memory controller which may use less power and/or space. It seems very interesting 1280sp (overclocked on 28nm) is essentially right beyond the scope of what 192-bit would be capable of even with fast/overclocked ram. Some engineer at AMD had his thinking cap on when maximizing perf/mm with this chip...now that we have something to compare it to I can see why they were so excited about it.
650 just makes me lol.
About a 650ti...kinda wonder if they will wait until Oland (or whatever the 8700 is called) to launch that. I gotta believe that will be somewhat similar (perhaps 896sp, 16rop, probably 192-bit/5gbps) and clock-for-clock a pretty even match-up to gk106 with an SMX disabled. I would think with those designs (and likely 130w tdp) the AMD part would be less logic and therefore able to be volted higher and max out it's clock potential (overlapping into the territory but not beating 660's potential), while the 650ti would be another ~1075 max chip that basically kills 8750...but we shall see.