The core branding and specs are what everyone is speculating about.
If it's suppose to be their flagship then it would've been named as GK110, just like how GF110 is for the Fermi GTX580.
And as you can see below, besides the GTX285 because that's just out of the question, the memory interface has shrunk.

Well it's all just speculation right now and maybe nVidia is trying something different, we don't know.