Currently, a rumor is circulating that various third party publishers will be releasing games that can only be played on the DSi this fall. These games differ from regular DS games in that they will take use of certain DSi exclusive features.
In order to distinguish these games, they will be packaged in a white game case instead of a standard black DS game case. The game cases will also have a warning letting consumers know that these games can only be played on the DSi. The DSi game cards will also have a white plastic enclosure matching the exterior packaging.
Presumably these games will take advantage of the DSi's stronger processors and increased RAM. It is currently unknown if the games will take advantage of the DSi cameras or SD card slot.