I've been perusing the photo gallery thus far and it looks like you guys really enjoyed yourselves at Dragoncon. I would have loved to been there but maybe next year. Can't wait to see the rest of the photos!!!
DC is held only in Atlanta. For a good bit of time now, the Hyatt Regency and Marriott Marquis have been the "core" host hotels, with occasionally other places used as well (previously the Apparel Mart [big convention center type place], this year the Hilton [just registration, though]).
Frankly, though, I wouldn't shed any tears if the Hyatt was dropped as a host hotel. The traffic flow during the busy periods sucks (to the point of the ATL Fire Marshall ordering the "wander around and gawk" level shut down due to the mass of people causing a fire hazard on Saturday night), and the security staff are frequently dicks.