A lot has changed since ten years ago - first and foremost the economy. It's not as easy for people to travel, take time off work etc etc to attend fan conventions. (The price of gas having quadrupled especially doesn't help). The people who really should most be able to attend wouldn't be able to be there...and even those who can get there may not have lots of disposable income to spend on stuff.
Another major difference: The Muppets are now part of a major corporate conglomerate, not a family-owned/operated company. The latter allowed a greater intimacy and accessability (heck, Brian Henson was spotted assisting with stuff in the parking lot - how many CEO's do stuff like that?) I'd wonder how hands-on of an experience an official convention would be...given the history of Disneyana, i fear it would mostly be more an excuse/opportunity to lure fans in one place to sell overpriced merchandise more than an actual celebration.
If one were to happen next year (i think 2011 is too early to pull one off especially given how in demand the Muppet team will be for the promotional blitz), it would also be after a major high profile project marketing with everything The Mouse House has got and the result would be a mix of hardcore fans and ones attending because they're The Latest Thing...in 2001, the fandom was more underground and the people attending were true blue (and green) fans.
If one were to happen next year (i think 2011 is too early to pull one off especially given how in demand the Muppet team will be for the promotional blitz), it would also be after a major high profile project marketing...
If it happens again, I'd try my best to go down. I mean, just hearing about what happened down at the first one is exciting! All those performers, the panels, the music, The Muppet Show Live?!!! I definitely want them to do it again!