I'll break these specs down into 2 sections. How they rate compared to the HD consoles and their plausibility of being real.
GPU: Custom AMD RV770 @ 766 Mhz on 32 nm process - 1398 GFlops
Compared to HD consoles: Much faster. The GFlops rating alone 6-7 times that of the HD consoles.
Validity: While TSMC no longer has 32 nm plans, GlobalFoundries does again. AMD used to own GF. The clock speed and GFlops rating suggest it is based on the HD 4870. I'd say this isn't likely due to the TDP but if it were dropped down to 32 nm, it might be possible to keep it cool enough in a console.
CPU: IBM Power6 @3.5 Ghz. 4 cores on 32 nm process.
Compared to HD consoles: Much faster. Power6 is much more efficient per clock than the Cell processor the PS3 and X360 are utilizing (yes, the X360 uses a Cell derivative).
Validity: Power6 was initially offered at various speeds including 3.5 Ghz but is now produced in the higher ranges (3.6 - 5.0 Ghz). Personally, I think Power7 is a more likely CPU than Power6. The 32 nm process raises a lfag as well. While IBM does offer 32 nm processing, it does so on their SOI (SOC) products and not stand alone CPU's.
RAM: 512 XDR2 Main plus 1024 MB GDDR5 plus 16 MB eDRAM.
Compared to HD consoles: Much faster and the volumes prevent bottlenecks and allow plenty of free AA.
Validity: No RAM manufactures are running XDR2 lines. Rambus (technical desingers of XDR2) is having incredible difficulty getting anyone to license it despite it being incredibly fast stuff.
Storage: 2.5" SATA HDD 250/320 GB plus SD and SDHC card expansion.
Compared to HD consoles: About the same.
Validity: Nothing to suggest valid or invalid. I personally believe the capacity will be near to exceed 1 TB given the incredibly low cost of HDD capacity these days which will only be better by launch.
Media: Custom Blu-ray, up ot 50 GB.
Compared to HD consoles: On par with PS3. Superior to X360. Bandwidth will be a concern unless part of the custom is much faster drive speeds.
Validity: Somewhat doubtful. Licensing from a consortium which Sony is the head partner is dubious. Especially when there are many competing optical disc mediums that would not require the fees to the Blu-ray Group and have higher drive speeds. And while it's just as dubious, it should be known that Nintendo invested heavily into a company that worked on holographic storage media.
Display: Various output resolutions
Compared to HD consoles: On par.
Validity: Most likely. Nintendo will want to ensure compatibility with HD and older SD TV's. As well as regional standards.
The rEVOLution is not being televised
