The 7000 series is a 7670, which is a rebranded 6670. MS will never put 8GB of RAM and and Octacore CPU in the 720 because, while 8GB of RAM is relatively cheap, an Octacore is not. That would put up the cost of the console to over FIVE HUNDRED AND NINETY NINE US DOLLARS, which worked so well for Sony, as we all know. This is even more important to consider when you realise that they're making it backwards compatible - that's another tri-core PPC processor to add in, that, while cheap, pushes the price up more.
If those specs were correct, the console would be seriously unbalanced - a shitty graphics card with RAM and CPUs most gaming PCs don't even have creates a huge choke point on the GPU. What the document actually said is the next Xbox will be able to be 'scaled up' to those specs - sensible given that they predict a 10 FUCKING YEAR lifespan. (They can't be serious with that 10 year prediction, surely?)
No, I predict we'll see 2GB of RAM and a quad-core CPU. For pricing mainly.