Folks have been waiting for this for quite some time. Microsoft has released the new version of Microsoft Reader that is optimized for UMPCs, and catch this, also Tablet PCs running XP Tablet Edition.
Some of the new touch enhancments include page navigation points in the left and right hand margins, a larger screen view in landscape mode, and larger context menus. Now if they can only do something about that ridiculous activation process.
Check out more and download the new version at the Origami Project.