I don't recall having the panel entry problem at Denvention 3 (2008 WorldCon), but definitely it had a different feel from other conventions I've been to. Less Big Media convention (StarFest, Nan Desu Kan), and closer in feel to Mile Hi Con (our local small Literary SciFI/Fantasy con), but with a definite international and business air to it. Well, to be expected, networking between authors and other professional sorts tends to occur at a WorldCon at a scale that you wouldn't expect at a lot of other conventions.
"You know how parents tell you everything's going to fine, but you know they're lying to make you feel better? Everything's going to be fine." - The Doctor