I looked at using the Windows Media Player as my current Media Player. I think the v9 beta is pretty cool.
Unfortunately most of my media files are encoded in the MPC file format. I looked at creating a directshow filter for mpc so that I could play my files. It turns out that although it is possible to get the actual audio to play using the directx architecture in windows media player - it is impossible for me to provide tag information (track number / title / artist /genre / album cover etc) to the windows media player and therefore the windows media library will not work. This to me is a very important function of a media player as I suspect that media libraries in the home will become more distributed using upnp (and I think MS's may be the first).
Does it not seem anti-competitive of Microsoft to not allow a media format other than there own blessed WMA format and MP3 to participate as first class citizens in the player. Most of the other players provide an sdk for input plugins. Windows Media Player will no doubt, in coming years, be installed on nearly every PC on the planet and WMA the 'pushed/blessed' codec in this application. This will mean that it will be harder for codecs such as MPC and Ogg Vorbis to compete.
What do other people think?