Mind enlightening some of us with details?
Shrug. It's just a super huge improvement to be able to configure multiple inputs/keycodes per FE function. I like how both P1 and P2 can now control the list, and it's super easy to configure too, especially if you've ever configured MAME's (old-style) ctrlr files.
Not only that, but it's so much more efficient to scroll through 5000 games using the trackball than it is using the joystick, even with page-up/down or letter-up/down. ..And to top it off, it's smoother than DK's scrolling or Kymaera's scrolling ever was on my machine (AthlonXP 2100).
-Steve
P.S. Even though this feature's been there for a while, I just got the CPViewer stuff working. I love it!