Well, I can't program my Media Center PC from my phone - well, not that I know of, but I can program in reminders to record shows and then add them when I get home.
The real benefit users of Windows Mobile have is that they can sync their programs from Media Center to their phones and watch them on the go!
However, Windows Media Player 10 Mobil is terrible for playing back video of any length. fast forwarding is painful and not practicle, also it doesn't/can't remember the location of video you left off, etc.
Do third party programs offer better playback features?
Back on topic now, how long before we see a Windows Media Center remote interface for the Mobile Phone market? (program, delete, etc)