I can't imagine that coming out anytime soon. Yamaha just released the Tyros 3.., and the replacement for the S-900 would be the baby brother to it. Yamaha would first want to rack the sales of the T3 before they release its baby brother to compete with those sales.
I would base it on the time it took them to release the S-900 after the Tyros 2 was released.
[This message has been edited by squeak_D (edited 10-22-2008).]
_________________________
GEAR: Yamaha MOXF-6, Casio MZX-500, Roland Juno-Di, M-Audio Venom, Roland RS-70, Yamaha PSR S700, M-Audio Axiom Pro-61 (Midi Controller). SOFTWARE: Mixcraft-7, PowerTracks Pro Audio 2013, Beat Thang Virtual, Dimension Le.