Since the Windows Media Center Edition screenshots its been apparent that there is an updated version of Windows Media Player included. Its build number 3005 and Tech-Critic have it for download.
The download is actually a upgrade patch for people that are using Windows Media Player Version 2980 and up. It will upgrade to version 3005.
FIX: New Option to Suppress All Dialog Boxes in the Windows Media Player 9 Series OCX
A supported fix is now available from Microsoft, but it is only intended to correct the problem described in this article. Only apply it to systems that are experiencing this specific problem. This fix may receive additional testing to further ensure product quality. Therefore, if you are not severely affected by this problem, Microsoft recommends that you wait for the next service pack that contains this fix.
ED - Its unclear if this build will be included with Service Pack 2
Download: Windows Media Player Update
DO NOT install this on Windows Server 2003! It doesn't work correctly..Thanks Bink