I've been to Columbus a few times and I was really impressed with the city. One of the best things about the city is its neighborhoods and how varied they can be which makes up the city's diversity.
Short North: the city's arts district just north of Downtown and OSU
on High St. (hence the name). Lots of art galleries.
Arena District: I'm not too familiar with this part of town, didn't seem like there was much there besides the area at the time, looked like they were still fixing things up.
German Village: cool place, can't remember the name of the place but there was this restaraunt that has some awesome bratwurst (and it's known for the creampuffs)...someone out there probably knows.
Easton - really nice place to shop. Nice stores and neat atmosphere as a pedestrian mall. Nice Barnes & Noble there, too.
Polaris - huge mall mostly made up of really expensive foo-foo stuff. I couldn't afford the stuff there for the most part.