And 400 years ago, opinionate was standard English, though writers in need of a verb meaning "believe, express an opinion about" could also choose opine or opinion. "Pythagoras opinionated [the soul] a Number moving of it selfe," says a 1643 tract cited in the Oxford English Dictionary. Opine has since pulled far ahead in the popularity contest, but that doesn't mean opinionate is dead.Well, whew for that. I thought for a moment there that we might have an illegitimate verb, and that would mean that ... uh ... well ... Well, someone's going to have to tell the President.
This kind of thing has a tendency to annoy those in the "we already have a word for that" school, which would hold that ipso facto the new word is illegitimate. As Freeman notes, the already-have word is opine. However, she comes to the defense of the "new" word by noting that it has a subtle distinction from opine; she notes the analogy of the subtle distinction between comment (what you and I do) and commentate (what people do who are paid to comment).
But words don't need to be justified by the lexirati to be "legit." Whether opinionate means exactly the same thing as opine or not, it's out there. One thing that Freeman does not mention is that opine is a stuffy word and probably not used much by ordinary speakers. And why should it be? The relationship between opinion and opine is hardly obvious, certainly nowhere near as obvious as the relationship between opinion and opinionate. It's not inconceivable that opinionate could even replace opine someday, and the latter could come to be seen as an archaic term. (Current Google count for opine: 5.2 million; for opinionate, a paltry 48,000.)
Extending nouns to verb them is a common enough occurence; we recently saw executionalize. And although the -ate suffix seems to really bug some people, it's a, you know, legitimate way to form new verbs. (hyphenate, disambiguate, etc.) When I was in the U.K., I picked up to orientate as a pretty common variant on to orient. I use it now and then, mostly for my own amusement, seeing as how it often gets a rise out of people. I did that the other day, and sure enough someone cringed. I could not convince them that it was a common usage in Britain.
Paul Niquette devotes a page to the topic of orient and orientate and, as he says, "marked the beginning of a personal effort to identify every potential 'misguided back-formation' -- verbs that might have been derived from English nouns ending in '-ation'..." And boy howdy, he does come up with quite a list: adaptate, administrate, admirate, adorate, ...
For laffs, we could ponder -- that is, we could opine -- on what other new verbs we might see some day:
evaluationate (Heh, wouldn't that be hilarious?)