New restaurant for Chicago visit
Graham Elliot is the new hot spot - we had a delicious dinner there the other day. It's a more casual vibe, but really refined, fun food but the former chef of Avenues. The cocktails are nice, too. If you can't get a reservation, we saw people eating in the nice, but not-so-crowded bar area. http://www.grahamelliot.com/
There is a new restaurant soon to open on West Fulton by the same guys who run Blackbird and Avec - a "gastro pub" which could be of interest. I imagine it will be quite good, although it's taking forever for them to open the place up. Maybe by the time you show up it will be here.
I'd also recommend Mercat a la Planxa on Michigan avenue which is the best new restaurant I've been to over the past year or so.
If you like Blackbird, you might also try Naha.
If you really want to go all out, Alinea is always an option. In a similar category is L2O which is primarily seafood. Or Schwa if you can ever get a reservation (and I've heard some kind of mixed reviews coming out of there lately).