IMHO there is not much improvement with OS-2.0. They included a lot of toys that most gigging musicians will find useless. I was personally hoping for a refined effects section with at least 6 or 7 independent DSP's, but Korg seems to be slightly behind the competition in quality of DSP's, as well as quantity. Furthermore, the useless quarter tone user scales should have been designed in the same way as on Korg Triton. Believe it or not, many arranger players world wide lug the triton around just because of the user scales. Another improvement could have been made with the BRASS section. I think that the trumpets and brass are weak in general.
Finally, OS 2.0 should have included optional keybed replacement for the pa800, and a user friendly software editor for easier organization and merging of SET's, styles etc.
Let's see what OS 3.0 looks like!
[This message has been edited by hitman (edited 12-07-2008).]