Ultimate Band allows players to play guitar, drums, bass or be the front man or woman in a band (though vocals are not supported). The Wii version follows the fortunes of an upstart rock band, with the player building the career of their customizable character, unlocking bonus songs, venues and accessories.
Ultimate Band forgoes the use of specialized peripherals such as guitar and drum controllers, relying mainly on the Wii Remote and Nunchuk for the Wii version, and the touch screen and stylus for the DS version. For example, to play notes on guitar in the Wii version the player must press a button combination on the Nunchuk while strumming the Wii Remote up and down. The DS version, based on Hannah Montana: Music Jam's code base, will also allow players to create and record their own songs, and have greater song customization options.
Ultimate Band features support for Disney Interactive's DGamer community network. The game will also feature connectivity between the Wii and DS versions, with DS players being able to control stage lighting and effects using the touch screen while a band performs on the Wii.
Source: Wikipedia, "Ultimate Band", available under the CC-BY-SA License.