From this article, an interesting quote regarding Bonnaroo from Umphrey's McGee's Joel Cummins:

"It's really important to have that progressive element and bring new things in. I'd love to see something like Dream Theater here that doesn't get as much exposure in the U.S., but is huge in Europe. You need to have that freshness. For fans to say 'I've discovered something new that I've never expect to see at Bonnaroo,' I think that's one of the things that bring people back here. It's the ones you don't know you're going to see that blow you away and keep you coming back."