Even if it were true that Sony was developing the move before the wii came out, what exactly does that mean?
Let me say that I'm sure it took more than a year to develop the Wii, so it could be said that Nintendo was developing the Wii before Sony was developing the move.
As far as motion gaming goes, before the move, before even the wii. GBA had two games that had tilt controls. Eye toy may be running with the video capture but aside from webcams- motion gaming was around since 2004.