Don't forget Spoodles, a night club on the Boardwalk. This is the home of the "dueling pianos", with 2 piano players/singers who do requests all evening. Actually there's a couple pair of piano players so, instead of taking a break, the music continues. We went there in May and it was fantastic.
A couple notes: There is a cover to get in, as I remember $10 per person. Later in the evening there were no seats left and a line to get in. Smoking is permitted, but ventilation is good. They don't accept the Disney room charge, so you need either cash or a normal credit card.
If we ever have a trip where we have to choose between Spoodles and the Adventurer's Club, it would be a really tough call!