And the clock strikes rumour o' clock. VG247 say that, according to "highly placed sources", they've learned why Phil Harrison left Sony. And it wasn't for an office door that read "Directeur Général Délégué". They say it was because development of the PS4 was about to kick off, and Phil just couldn't bring himself to go through the whole thing again.
He could see he was about to get involved in another PlayStation cycle, and obviously wanted something new. The same thing was happening again and he'd been through it enough times to want to move on.
May be true, may not be true, either way, it's a possibility. We're just surprised Sony took so long to get started on the PS4, seeing as companies normally start on their next console as soon as they're finished the last one.