id like to chime in on wizard world...first off ITS NOT A COMIC CON!!!! its an entertainment con and because some of the entertainment is comic related there are comics. I'm not sure but i just looked at the website and they don't call themselves a comic con.
second i think reed pop who does C2E2 ( my favorite), emerald city and NYCC does it the best because they have more than half of the show with comic vendors and writers/artist and they are not entertainment focused and that is a saving grace.
i do like the small local shows in rented out union halls or ballrooms here in near st louis we have 2-3 which are super fun! one is toy man toy show and its all comics, toys, gaming, hot wheels and a lit more. and there is another show that is all comics in a rented VFW. and another comic book show INSIDE a comic book store.
so when will the comic con bubble burst?...well I'm not Adam Schiff but unless comic book movies stop coming out there will always be a show will, wizard world still be hear (i hope not) who cares don't go!