Pentax just announced a new firmware v1.01 is available for the new camera:
http://www.pentax.jp/english/support/digital/k-x_s.html
Changes to V1.01
* Added three kinds of particular effect shooting function (Pre-set 1,2 and 3) on [Cross Processing].
* Added assignment of Cross Processing function to the green button.
* Improved accuracy of Battery Level Indicator under specific conditions and improved stability for general performance.
Cheers all K-x users
http://www.pentax.jp/english/support/digital/k-x_s.html
Changes to V1.01
* Added three kinds of particular effect shooting function (Pre-set 1,2 and 3) on [Cross Processing].
* Added assignment of Cross Processing function to the green button.
* Improved accuracy of Battery Level Indicator under specific conditions and improved stability for general performance.
Cheers all K-x users