The only respectable form of the word is the noun "incentive."
I hope everyone who says "incentivize" in earnest knows they come across as a jargon-spewing ahole.
Why they can't seem to cope with this much simpler word, I don't know.. obviously doesn't sound important enough.
"This bill will help incentivize everybody to solve that part of the problem” (Richard A. Gephardt)."
How absurd is that. Gah.