According to VG247, 'highly placed sources' within Sony have let slip of the real reason why Phil Harrison decided to call time on his Sony career. And oddly, it's because of the PS4.
"He could see he was about to get involved in another PlayStation cycle, and obviously wanted something new," said the unnamed source. "The same thing was happening again and he'd been through it enough times to want to move on."
It sounds logical that Harrison might just be a bit sick of the whole thing by now, and him coming out and saying he's taking off because of the PS4 wouldn't have exactly helped sales of the PS3.
Then again, this could be one those 'unnamed source' things that's a big old load of crap. Thankfully this blog thing lets me get away with posting that kind of thing. Phew.