The statistics are released. The FIQ – International Comic Book Festival, held in Belo Horizonte, Brazil last month is the largest comic convention in the American continents. With 148,000 beating San Diego's capped 130,000 attendees.
It may pale against the likes of Japan's Comiket and France's Angouleme, but it's a lot closer for the average American than either of those shows.
It's also worth bearing in mind that FIQ just covers comics – not games, not Hollywood studios, not TV, not Twilight. Just five days of comics from 9am till 10pm. And they had thirty thousand school children show up through the show, a mix of vendors, panels, exhibitions, signings, sketching, workshops and the like. They had Brazilian creators, and creators from around the world, including an official DC prescence and an official Marvel prescence at the show, where they announced a bunch of Defenders news.
The next show will be in November 2013. You might want to start looking into tickets now. I know I am. Here's a quick look at what I missed.