I go to live shows for the total experience, but with the kinds of music I'm most into, it isn't about showmanship as it's usually defined. Instead, it's about the vibe that the performer puts out as they're doing their thing. Seeing the people whose music I love do what they do has an effect on me that I can appreciate almost as a part of the music. Some players are a blast to watch in terms of interaction - think Astral Project and Pilc/Hoenig here. There's an intensity and humor going on that doesn't make it onto the records in the same way, or at least maybe I'm just too dense to hear it until I've seen it. I'll never forget "seeing" Fred Hersch's great trio with Drew Gress and Tom Rainey and the trancelike states they'd all get in. That made an incredibly lasting impression on me.
In the end, I wasn't made to be a very good showman. Something's missing in the genes for that. But after seeing a lot of greats play and watching the way they express themselves physically and the way they relate to the other musicians on stage, I can honestly say that I've learned a lot about what to do by what i like seeing others do. When guys smile at each other onstage in an honest way, that's a good thing. When players like something somebody else onstage is doing and show it in their body language, that's a good thing, too. The reverse is also true in that you can learn a lot about what *not* to do if you find certain gestures/habits to be phony or cheesy. With this in mind, I like hearing and seeing live music happening.