The ability of the human mind to rationalize anything if the rewards are great enough has been proven time and again. If you give someone enough incentive, and ease them into it slowly, a person will be able to justify anything to themselves.

The more they're challenged, the more justifications and rationalizations they'll come up with to defend their choices, and the more entrenched they'll be in their new position.

Far greater people have devoted more than a single decade to M$(and other companies) in exchange for cash. It's not unusual. It's called capitalism.

Depends on the bribe.

Everything he has ever done for FOSS is a waste of time. Bonobo and Mono are utterly pointless. It might not be a direct bribe but taking MS' money via Novell and pissing ten years on it is exactly what I expect from a developer of Miguel's caliber [sic].