It's amazing that just a few short months ago Apple and Google were not competitors in anyway, but in that short time Google created so much new software that the conflict of interest would be too great and he was forced to resign. Or..., Schmidt is an arrogant ass who didn't want to listen to those calling for his resignation, and wanted to leave on his own terms.
Still though, the announcement of the yet-to-exist Chrome OS surely was the deciding factor.
Jackass.