The plugin would be fairly simple, I would think, and you could make the functionality exactly like the PowerPoint Remote Buddy settings:

Play/Pause: Command-L (Enter/exit full-screen mode) 
Right: Right cursor arrow (next slide) 
Left: Left cursor arrow (previous slide) 
+: Command-shift-up cursor arrow (first slide) 
-: Command-shift-down cursor arrow (last slide)

Since I present in Acrobat fairly frequently, it would be great if you could add this functionality.

Finally, thanks for a great application! I just paid.