There's a way I could see this maybe working but not nearly as granular as he wants it.
You'll need to separate the things logically. All the high-speed stuff will need to be in the same block. CPU/GPU/RAM would all have to be in the same block and provide an external USB and LVDS interface. The radio would interface over USB as well as the camera. Storage is easy, just use MicroSD.
The problem comes is just like a real computer, you need drivers. Unless they figure out a way to provide a generic interface where the block only communicates on a high level.
Problems:
1. Phone would be bigger than now
2. Phone would be more expensive because of less integration. If Qualcomm could make a single chip that does CPU, GPU, RAM, RADIO, BT, WLAN why not?