Kid Icarus: Uprising was originally slated for release in 2011, but was delayed to Q1 2012 by Nintendo. Director, Masahiro Sakurai, tells Official Nintendo Magazine that when the game releases, it will also support the Circle Pad Pro attachment.
Using the game’s regular controls, you’ll use the touchscreen to aim and rotate the game’s camera, and use the Circle Pad on the 3DS to move. Once you attach the Circle Pad Pro, you’ll still use the touchscreen for aiming, but you’ll be able to use the Pro’s Circle Pad — which is placed on the right-hand side of the system – to move.
Sakurai says this option was added to support left-handed players. He explains that he didn’t know about the specifics of the Circle Pad Pro until the device was announced alongside Monster Hunter 3G, which is why his development team, Project Sora, didn’t have the time to implement it in any other way.