When you're watchng a single Video file (like a TV Show) the SKIP button is a 30 second jump. When you're watching a DVD by default this button skips chapters, but in the DVD Settings you can change it back to work like it does when watching TV.
I listen to a lot of Podcasts (like this one) and I wish I could do the 30 second jumps when listening to audio as well.
Same things goes for the replay too of course. I want to be able to jump bck and forth in Audio.