Kevin Smith has had a panel at almost every Comic-Con since for the past umpteen years, and the line for it is always out the door, around the corner, down the block, across the street, and stretches into Mexico. You can be sure of one thing at most Cons, and that is the fact that you're going to need to line up early to get into this thing.
Wait, I meant to say you can be sure of two things. One, line up early for anything Kevin Smith related, and two ... be prepared for a lot of swear words. This really isn't the sort of thing you want to be bringing your seven year old daughter to in her Pokemon costume unless you want to be explaining some fairly graphic things to her. If you do, get ready for an incessant stream of, "Daddy, why is everyone laughing?" Although the eleven-year-old kid in front of me sure seemed to get a lot of the oral sex jokes. Wow.