Looking at this from an ecnomic perspective. For the prices that are unannounced, I'm taking a guess.
The PSM is going to be very expensive for a multiplayer setup. Even the Wii is a fair amount for multiplayer.
PSM
PSM basic kit: $100
Nunchuck: $20-30
Lightstick: $40-50
Full one person setup for PSM = basic kit + nunchuck+ extra lightstick + PS3
Full setup for each additional person full setup: lightstick + lightstick + nunchuck
Natal
Natal camera: $50-100
Full One person setup for Natal = Natal camera + X360
For each additional person: Nothing
Wii MotionPlus
MotionPlus: $20
Wimote/WM+ bundle: $50
Nunchuck: $20
Full one person setup for Wii M+ = MotionPlus + Wii
For each additional person full setup: Wiimote + WM+ + Nunchuck
Anyone can guess. It takes no effort to throw out lots of predictions and have some of them be correct. You are not and wiser or better for having your guesses be right. Even a blind man can hit the bullseye.
