Not to invalidate most of what you said... but FFG was certainly not a bigger 'gaming area' than WOTC had. Sure, in the Dealer's Hall, but WOTC had a huge chunk of the Card Hall, and a large chunk of the second floor devoted to it. Sure FFG had some big stuff in the open gaming hall, and I'll concede that visuals in the Dealer's Hall is a big deal, but compared to WOTC? Not a chance...
That being said, I've -heard- and even seen some not terribly reliable sources that FFG's 40k line is hands down the second biggest RPG in the world, and by a rather large margin. Only D&D competes, which doesn't shock me in the least (I'll be shocked if D&D is ever in 2nd place for long, maybe for a few months in the lead up to 5th when people don't want to buy new 4th... but yeah. The simple fact FFG can even come close is impressive!). I'd love to actually see some articles, but it's a pain in the bum to find them, given how many other things RPG pulls up that are much more mainstream.