who's it gonna be?

Hmmm good question. I would love to see Les Claypool sit in with anyone....maybe Beck or Cypress Hill..that would be interesting. Trey sitting in with Umphrey's would be pretty sweet. Any mixing and matching is always good in my book;)

ok ok ok, phil and friends, I wanna see trey get up there and get into some viola lee blues

Thom Yorke and Johnny Greenwood sitting in with the Biscuits would be pure unadulterated madness

I sincerely hope Robert Randolph runs around as much as he did last year. Trey has friends everywhere, and I think Ben Folds might turn up here and there. Wouldn't mind any combination of Phil/Petty/Costello/Buddy Guy.

i am hoping that beck plays with oysterhead for the simple reason that it would mean they wont both be playing at the sametime....same thing with lyrics born and umph/bisco on fri

i agree radiohead wont do guests. but how cool would it be to have trey sit in w/ them for a song. That would be unreal.

I'd love to see Les sit in with Bela Fleck so that he and Victor Wooten could have mad bass sex together

Yup, Popper should be out and about, wouldn't mind hooking him up with some of the old-timers at roo, Buddy Guy, Petty, or Costello especially. Bonnie Raitt could come out in one of those combinations as well, she is an extremely well respected female vocalist/guitarist who I'm sure has worked with at least one of these guys before.
Ben Folds and Dr. John, dueling pianos?
Common and Cypress Hill (as far as I guess) will probably be the only two hip-hop style acts with a stage. I doubt Cypress Hill, but probably Common will invite someone like Gift of Gab or Lyrics Born on stage.

Les guesting with Radiohead for a nice extended version of "the national anthem"....i think i might just die......or......Thom droppin in to guest on "Radon Balloon" w/ oysterhead.......both of which wont happen, but we can dream cant we?

i think ben folds will do the guest star thing a lot, he's a great performer.

y ai cant even believe popper popped up at roo. i was under the impression he died any years ago. but i am happpy he didnt and i cant wai to see them. trey will play with phil, even with scofield i would say its almost 100 percent trey will be there.

I don't expect anyone to sit in with radiohead, but wouldn't be that surprised if Beck joined them for a song or 2.

It's happened before:

I can see ben folds guesting with a lot of people, including Les or beck.
Andrew bird with the Flecktones would be tight, as would DeVotchKa with Matisyahu.
I think Buddy gut has a good likelyhood of showing up in a lot of high profile sets, incl. the headliners (except for radiohead), Bonnie Raitt and Costello as well. I think this year will see some very interesting combinations on stage. And don't forget that Oysterhead was origionally a one-off superjam at NOJF.

andrew bird can play soooo many instruments he's very versitile and will probobly show up a lot.