My husband has performed in several of them - he plays piano and sings. Last year at CSA he was the only guest participant! At COR (as it was then) he did a song on his own, then joined 2 other guests and the band for one.
We've seen mostly musical talents, but I've heard of people dancing.
I have played the keyboard several times in the talent show. I have also seen folks sing, dance, and once we even had a martial arts demonstration by one of the guests. They are a lot of fun to participate in and the band members are all very good musicians. Cornell plays the guitar when he is there.