There will be 4 new DLC packs for Dead Rising 2 released within the next month or so.
Each pack is a different theme. There's the Psychopath Theme, Soldier of Fortune Theme, Sports Theme, and then Ninja Theme.
Each pack will feature new skills, weapons, and outfits. Players are able to mix and match the outfit items from each patch. (i.e. could wear psychopath's shoes with Ninja trousers)
The Psychopath Theme is the first to be released of the four; October 12th for XBLA players and October 13th for PSN players. The three remaining packs will be released weekly. They are priced at 160 ms points or £1.59/1.99 euros per pack.
These will also be released for the PC version, however, the dates are unknown.
We have posted a lovely review of this game if you need further information.