I had the distinct honor of going to Jambo in 97 as a particpant, and in 2001 as a staff member.
I would highly encourage you to do both. It's a wonderful time, and both experiences are vastly different.
'97, I grew up. A lot. Jamboree really helped me mature as a young adult.
In 2001, I went back as a staff member on the Fire Department. That was the most fun I have, and even got to help save a couple lives along the way. My engine company was first due for the scout who was struck by lightning. I will *never* forget that experience.
Go, go. I won't be able to make 2010 as staff, and for that I am deeply saddened, but I will make it there, one way, or the other as a visitor.