An “unnamed Japanese developer” has told Wii U daily that Nintendo’s next console will contain:
1 quad-core 3GHz PowerPC-based 45nm CPU
768MB of DRAM “embedded” with the CPU and shared between it and the GPU which is 40nm and ATI-based. Try saying all of that three times really fast while holding your tongue. 

The site’s source claims to be working on porting a PS3 game to Wii U, and that Nintendo is currently testing another version of the console with 1GB of DRAM embedded with the processor. 

As usual, just file this away for later use until Nintendo officially announces specs