Before I pick the hardware, I will explain it in terms of hardware that would exist if they used a similar mindset to produce a current generation console ... The GPU would be similar to using a Radeon x800 or Geforce 6600/6800 as your GPU, the CPU would be similar to a PowerPC 970MP @ 2GHz, and it would have 512MB of (moderately) inexpensive ram if it was released in 2006.
The hardware that I think this will relate to is a multi-core Cell processor (for Sony) at 4.5+ GHz, and Power6 based CPU (for Microsoft/Nintendo) also at 4.5+ GHz; the GPUs will (potentially) be based on the next generation of Graphics cards (AMD HD4870/Geforce GTX 280) with some modifications (like increasing the number of stream processors); and there will be 2GHz of Memory. (This is assuming a 2011 release date)
