Non-Mac-Supported-Content on DVDs?



What's up with with this Non-Mac-Supported-Content on DVDs? I have heard mixed stories and fingers are pointing in all directions. Is this missing content available on set-top DVD players? Does it really matter - besides looking bad for Macs?

I welcome any and all opinions and facts on this one.
Yes there are some PC specific features on DVDs. Our Matrix DVD is one of them. We watch all of our DVDs on our Playstation 2 on TV though, so it doesn't matter to us. I'm sure some other folks would be shaking their fists though.