Namco Bandai USA's Facebook spill the beans.
There's a chance they will sell the DLC characters instead of giving them for free since this promotion's similar to Namco Bandai's retail of the game in Japan. (Kira Form One was a pre-order bonus for the Japanese version). I hope the DLC is free, since this isn't a high-demand game. Unlike the Japanese version though, there will be an arcade mode and the patches for Campaign mode will be added.
WWWRRRRRRRRYYYYY for now.