@Sven Groot:+1 this. Although I'm not totally happy that optical media is going away - it has its uses in certain scenarios (copying learning tracks so I can play them in the car for example).
I think there were a number of parts to the decision to remove the CSS codecs (although I don't have firm information). First off, many/most video cards already sell bundle playback software - that means that most customers already have DVD playback capabilities (I know that every video card I've bought in the past few years has come with a WinDVD copy). Second, an ever increasing percentage of Windows sales come from volume licensed customers and I believe that CSS is licensed on a per-unit basis (reference)- per-unit license fees are a challenge in a volume licensed world. Third (as several people have pointed out), shiny media is on the way out - more and more machines don't have shiny media drives these days and that trend is increasing, not decreasing - there's no point in buying a DVD playback license for a Surface RT or Surface Pro device after all.
I actually like the solution MSFT came up with: Sell a low cost add-on which enables DVD playback for any customer that wants it and you're good.
Having said that, one thing I'm upset about: Windows no longer have DVD burning in Windows 8 which means I can't create DVDs of the videos I take of my wife's chorus concert without using 3rd party software.