They sold out in 1999 and have been taken over by the movie studios.
They run out of all 4 days passes before the event and have ZERO 4 day passes on sale day of - which sucks if you're someone without a credit card - like a kid.
The place is too crowded to walk on the floor - and the big panels are almost exclusively just commercials for upcoming movies (remember the Stealth panel, or the Good Luck Chuck panel??)