I think this will end up superior. Would it have less total bandwidth with the rumored specs even with the 2400mhz effective memory? Yes, yes it would. But G92's architectural enhancements (textures etc) over G80 and sheer clock speed should allow it to usurp the former high-end. Yes I understand people have already done this through overclocking current G92 products, but what matters in the market is the stock clocks, and on these products they are relatively higher than what we currently see.
That again all being said, it has been mentioned that this generation was supposed to be launch Q407, a normal ~1 year between high-end products, but was held back when there was a surplus of the G80 products in the channel, even at the reduced price.
My assumption has been that the 8800gt/s were only released because of nvidia needing products to compete with the 3800 series and now that excess G80's are out of the channel, they can go ahead with the launch of the products clocked higher and with more bandwidth at stock to actually call it the generation after the 8800 series.
I would just think of it this way...If you grabbed a 8800gt/gts512MB, you got to jump on the next-gen train early. If you overclock, you have defeated nvidia's intention, with the exception of the new highest-end part using faster memory than what is currently available.