i think what will happen is that the arranger/workstation will be the default keyboard that can be purchased. The divsion between workstations like the Korg M3 or Yamaha XS and say the PA2X and the Tyros 3 is created simply top hgenerate separate streams of income for the companies and the differences between the two types of machines deliberately maintained for profit reasons. If you never use the arranger section on an arranger keyboard then you are left with a very good if basic workstation keyboarc which in live use is indistinguishable from its "workstation "cousin. What i believe will happen is that the content of the arranger workstaion of the future will be completely customiserable (new word) and customers can purchase the content that they want for their instrument based upon their needs rather than buying a boat load of styles they may never use.

There are many arranger playing musicians that use their keyboards live sometimes with the arranger functions activated , sometimes without and we are already seeing traditional workstations beggining to morph in basic arranger keyboards. If i were to make a prediction i see only one keyboard type emerging and it will be an arranger workstation but perhaps not in the form we currently have it. It will have more highly advanced effects, sequencing, computer intergration, ease of OS updates and compatability with commercial production software but all these additional bits will be optional.