There are lots of fabs, and NVIDIA/TSMC isn't the only player. IMHO, we're getting to the point where the integer cores are supplying all we need for 99% of what they're good for. Everything else, such as video encoding and decoding, audio, gaming, UI and animation is leveraging special purpose areas of the silicon that do the job far faster than integer cores could. For example, everything I named above is accelerated by the dedicated SIMD, graphics or video decoder portions of Apple's A4 chip. The integer core is relegated to being the scheduler for the really high-speed stuff.
Looking thru the comments...page 5...2nd from the top ...lot's of detail but note this statement:
Don't believe what Nvidia is saying (that dual channel isn't required). They know its required but for some reason couldn't get it into this chip.