I expected to see an explanation on how they removed the bottom chin… where do the driving electronics go?

Wow! This unrepairable mess of glue, glued-down battery, screen that comes apart if you disassemble the phone and booby-trapped boards you have to remove very carefully is considered a 7? We live in though times.

"and the OMAP3? why?"

They had lots of them lying around because the Motoactv sold so poorly?

Ok, jokes aside, I believe the whole circular assembly is a pain to design and build cost-wise, so they chose the cheapest SoC possible to bring down the cost a bit. Bad choice.