With the Wii MotionPlus attachment being released on June 8th and the first Wii MotionPlus compatible game, Wii Sports Resort, not being released until July 26th, GameDaily theorized that Nintendo would release updates that would allow older games to take advantage of the MotionPlus’ capabilities.

However, Nintendo has debunked that theory, stating that the MotionPlus was designed for use with games “designed to make use of its abilities.” So it seems as though the MotionPlus will be relatively useless for at least a month unless Nintendo decides to make use of the attachment some other way.

[Source]