Yamaha are predictable. S900 sep 2007.
S910 sep 2009 .. And tyros 3 and 4 had
A 2 year gap instead of 3. This is why
I believe there is surely a S9XX in
Sep 2011. Another reason is one could
Argue the s910 was a semi upgrade. The
Keyboard coming out this year will be
A more significant upgrade..and due..