This has been posted on Gamespot:
What I have put here is 99% the real cpu/eapu specs.. This is Microsoft goal. It is also what is available in the dev kits that are at E3.. If Microsoft show the Durango/720/8/loop this is what is behind these specs.. The final 2 gpu design final spec is not 100% known out of Microsoft rnd there target is HD8970 tech. The cpu pic is the real durango cpu/eapu but now that specs are leaking out over the next 4 days. It shows you the future.
Durango cpu specs
SOI -28nm 22nm by 2014
3.8ghz - 4.2ghz Turbo-core mode
4 SMT every core
1024 KiB L2 per core
8 VMX128 cores
120MiB EDRAM
There is 2 cores in every core. they are not stacked cores.
Durango cpu is an ultra enhanced apu,
DX11.1- 12.1 Upgradeable core logic
"BASIC" Durango cpu can support 12- 32/64 bit 1080p Render Targets "back buffer" 10/64 bits color and aa on all back buffers. 2k resolution and beyond. Cpu/apu and gpu/s can access the EDRAM on the fly. A massive amount of system Ram is also available "more then orbis" (note: suddenly PS4 could have less ram then Durango)
Summary : 8 Core (2 core per Core ?) = total 16 Core x 4 Thread
picture of Sample chip
http://misterxmedia.livejournal.com/