Quote from rmohns:
Any sign on the circuit boards of the hypothetical DSP that has been proposed as required for the voice control feature?
The ARM chip is based on the the Cortex-A8, which includes a powerful DSP called NEON as a built in part of the A8 chip architecture. It doesn't need an external DSP. The A8 and NEON were announced several years ago, you can google more info.