Ubisoft's Wii version of James Cameron's Avatar will have MotionPlus support for specific portions of the game that'll use it.
Up until now MotionPlus projects have either required full use of the technology (Red Steel 2), or just added that extra layer of control (Grand Slam Tennis, Virtua Tennis 2009), however in Avatar there'll be specific MotionPlus-only sections that can be tackled in different ways.
For example in a preview from IGN, there was a section in the demo where there was an electrified door blocking off an entrance to a bridge over a large chasm. Those without MotionPlus could travel along the rock ledges, however those with the add-on could control a hornet through a hole in the fence to shut down the electric door. Both work, and at the end of the day will get you to the goal but allow for totally different gameplay mechanisms.
Be sure to check out the IGN preview for more details.
Do you think MotionPlus-specific sections is the right way to implement the technology, or should the entire game be MotionPlus-only?