2012 Convention Season has a lot going on, especially with some recent notes about multiple events in Indy during GenCon.
U*Con (Nov 11 - Nov 13): This is an annual event for me and I welcome you all. Hosted in Ann Arbor, MI it's one of the best regional cons I've attended. http://www.ucon-gaming.org/
Origins (May 30 - Jun 3): I know some people are upset by the date change, and hopefully it won't collide with Memorial Day, but I am glad there is some distance between Origins and GenCon. At least this year, May 30 works perfect for me.
DEFCON (Jul 26 - Jul 29): Not a gaming convention, but one I still need to attend. This year it was at the same time as GenCon and having to choose was unfortunate. In years past they have been back to back so getting some distance with GenCon is also good. If you are interested in Information Security, there are few conventions that can compare, and from a value perspective there are none.
GenCon (Aug 16 - Aug 19): I like this a little later in the month, especially since I attend DEFCON as part of my day job. Unfortunately, this year the MotoGP is going to be at the same time so there will be a premium on space. I think hotels don't allow reservations outside of a 330 day window (at least that's what one site reported to me), so mark your calendars for 9/20 to see if you can get a room. Check the links below for a discussion.