Never had the chance to sit on a table with a pro yet, but I have met a few already such as Phil Ivey, John Juanda, Howard Lederer who all gave me an autograph on a Full Tilt Poster, which hangs in my room now right above the PC where I am usually playing poker.
John Juanda was the friendliest one of them who immediately asked: "How are you my friend etc." Phil Ivey looked a bit bored as usually and just doing his duty by signing autographs but wasn't really in mood for small talks I guess.
Furthermore I also have seen that day Gus Hansen, Clonie Gowen, Chris Jesus Ferguson, Allan Cunningham, Erik Seidel & a german pro whose name is Eddy Scharf. But all these pros I have seen from a bit more far distance and couldn't get so close as to the ones who gave me the autographs. Was still a nice experience to see all of them and I hope I will have the chance to play some of them as well in future.