Never been to Comicon proper, but if it's like any other comic con I've attended, there will be abundance of recylced air which dehydrate and drain you considerably. Of course, that also means lots of restroom stops, but it's part of the game.

Also, if you actually plan on **buying**/paying for stuff, make sure to have enough cash on you before entering the fracas, because the ATM machines at these things always break down, and a lot of the sellers only take cash.

I just consulted with a good friend of mine who's covered the event professionally for the last four years or so. In his words: "Simple answer: MAke a list of things you REALLY want to see or do and then plan on only getting to a tenth of them."