One thing that struck me when watching videos of November 2011's Minecon was the large number of young attendees at the conference. Minecon 2011 was crawling with kids!
I'm not sure how Minecon 2012 compared to 2011 regarding the age of attendees. I only watched a single video from Minecon 2012 covering the API session, and during the Q&A there were a number of questions from kids. Being children they had a bit of trouble staying on topic, often asking questions about future developments in Minecraft itself rather than about the forthcoming API.
One blogger noted that the Q&As:
…meant sitting through a variety of children asking redundant things that have been answered a hundred times over, but you have to bite the biscuit on that sort of thing. The convention certainly opened my eyes to the volume and variety of people playing this game. Many of them are children, which just highlights the need for mindfulness, particularly when playing on servers. You’re probably surrounded by at least ten or so minors under the age of 12.
Here's a report from an attendee mentioning both autographs and kids at Minecon 2012:
Most of the panels were not informative at all, for example the Editing Panel were just them saying; “We use this software, and this” and answering questions from 10 year olds, asking why their video had black bars…Minecon is pretty expensive, but there were still a lot of kids around, but that is just a part of the Minecraft community. We spent a lot of time with Martyn (InTheLittleWood). And we could not walk for 10 min without 7 people wanting his autograph.
A year ago in Las Vegas the young fans at Minecon 2011 worshiped Notch like a god and stood in line for hours to get his autograph. Notch and other members of the Mojang staff spent considerable time signing autographs. (Minecon 2011 sold out with an attendance of 5000, and at the time I recall hearing reports of some disappointed fans who left Minecon without an autograph, but I can't find sources for that now.)
Apparently this year's Minecon 2012 had autograph lines too:
Oh man why did I stay in a line for an autograph while I could've attended Sethbling's panel
I've never attended any gamer-oriented gatherings. Do people wait for hours in autograph lines at QuakeCon, BlizzCon, or PAX, or is this only a feature of gatherings with large numbers of young attendees such as Minecon?