My wife's cousin is married to a Hamilton PD officer. We were sitting around talking by the pool at a family gathering last night (just the menfolk in the family), about everything from cornbread recipes to the economy to guns. We discussed OC too. He doesn't support it, wouldn't do it himself, and grudgingly admitted it's "probably not illegal".
Interestingly, he also mentioned that "no guns" signs mean very little, and ignoring them would "get you a simple trespass if anything".
I'll also report here that I OC'ed my 1911 on Sunday while walking the baby in the stroller in Fairfield. We went down Pleasant Ave, Magie, Fairfield Ave to Symmes, and back. Smiled and waved to a few people, helped a lady find a house for rent, and had no negative encounters to report.