Since I missed ORIGINS to attend my daughter's graduation from FIDM, and just because I've never been - I attended GENCON in Indianapolis …
Wow! What a huge event … Mostly run very well.
There were game and seminar events spread amongst the entire Convention Hall areas, amongst the meeting areas and ballrooms of multiple hotels within about a three or four square block area … as well as inside the Indianapolis Colt Football Stadium including filling the entire field area.
Admittedly, wargaming is not the focus of GENCON however I thought there were a good number of wargaming events and all I attended were well attended (and we'll run).
I played COMBAT INFANTRY (CBG), AGE OF SAIL (ARES), JAGDPANZER (tank skirmish mini rules - 2012 Jeff Gullion), Fletcher Pratt's Naval Wargame (ww1/ww2 naval surface combat mini rules - 2011 John Curry), FOG OF WAR (Stronghold Games).
There was a nice walkthru "museum" with displays showing programs, games, and photos from the past 50 years of GENCON. Wargames were well represented as were D&D.