wm+ can only measure your distance to the tv when you're pointing at the sensor bar, move can always tell the distance by the size of the ball in camera view. Move recalibrates continuously as long as the ball is in view. If not it will still work for a while but slowly start to drift.
Tumble can't be done with wm+. You can reach around and grab blocks from behind with the move, pointing the laser pointer at the camera, something that does not work with wm+. But that's about the only game atm where it really makes a difference.
Minor differences are noticeable in sports champions. Table tennis takes your distance and position to the table into account in gold and platinum difficulty. wm+ doesn't know where you are in the room.
wm actually has a better pointer, no plus required, as long as the wm has a good view of the sensor bar. Move can drift a little even with the camera correcting while wm always has a stable reference point. Pointing/shooting with your hand resting on your leg works better with wm. The minor movements are not enough to keep the move pointer completely stable.
To sum up:
WM+ measures 3d movement, orientation and distance to tv when pointing at the tv, doesn't know where the wm is in the room
Move measures 3d movement, orientation and position with continous recalibration
Both severely lack games that really make use of their capabilities :(
