Blizzard recently confirmed via a post on their official site that Jay Mohr will be hosting BlizzCon 2010 in Anaheim, California October 22nd and 23rd (we originally reported this via Jay's quickly deleted tweet back in February). Tickets go on sale for the event on June 2nd and June 5th for about as long as it takes to punt a gnome across the road. But if you don't get tickets, you can still catch Jay (and all the other glories that are BlizzCon) via the live internet stream.
In my opinion, Jay has been doing a better job at BlizzCon each year he's hosted. Some people really don't like him, and that's okay -- he'll just make fun of it.
Update: The curious story of Mr. Jay Mohr at BlizzCon continues. On Twitter, Mohr currently says he's not sure he's doing BlizzCon this year.