Far more interactive than Hoop-De-Doo. In a nutshell, there is a main salon (with a bar) and three attached rooms. Throughout the night, characters perform scripted skits in the attached rooms--a bit like Hoop-De-Doo, but the smaller crowd allows for more interaction, and, to be honest, the humor is more adult. (OK, it's been years since I went to HDD, but I still feel comfortable making that generalization.)
However, in the main salon, the characters will just walk around and strike up a conversation with guests. The comedy is pure improv, and the performers will crack you up. They also perform various "ceremonies" throughout the night; not only are you expected to participate, they will mock you if you do not.
I should also mention that there is so much to look at on the walls of the Main Salon that, even if there were no shows, you could still spend an evening drinking there and not be bored.
Definitely worth visiting--you either love it or hate it, there seems to be no middle ground. Don't forget you can come and go as you please, so feel free to leave, take in a show at the Comedy Warehouse, then return. I'm with DisneyDave, tho, AC has better comedy.