Gen Con just announced they are staying in Indianapolis, Indiana until at least 2015. The links below are more about the convention center than Gen Con, but the extensive upgrades and renovations apparently encouraged Gen Con to stay a few more years.
I did find it interesting that Gen Con is the 4th largest convention in Indianapolis. It is such a zoo that I wonder what number one is like? The hotel situation alone is enough to make one cringe at the thought.
Trask, The Last Tyromancer