I had an interview there, so I've been thinking about this:
Pros: large, so lots of opportunities both professionally (specialties, etc.)and just in general as far as campus amenities and activities. The facilities seemed pretty good. The students seemed nice, and they spoke a lot of helping each other out and being close knit. I liked the interview process, and Columbus was pretty nice (my first time there) and seemed affordable.
Cons: A little much with the school spirit for me. The OH-IO chants and school pics on every single wall. I prefer more subdued enthusiasm. Some people may like this though. Large, so a better chance to get lost in the crowd, harder to get around, etc.
I'll be interested to see what others have to say.