For some reason the video thumbnails are not shown in the Media Center
(folders or fils). It workes fine in explorer and media player but not on VMC.
I did not have nero installed on this PC (ever).
It happened after I added several video sub-directories and removing these
directories did not fix the problem.
The setting of PerceivedType="video" for all video files in the reg are
correct.
Had Divx and Xvid (latest verions installed). removed and installed FFDSHOW
(two different versions) and no change.
Anyone ???

I have exactly the same problem, but only with MPEG-2 video files. I even installed clean copy of Vista (without any additional software) and the issue does not change.

I have just searched Microsoft Knowledge Base and found, that it is well-known bug in Windows Vista (both 32- and 64-bit editions), without any solution till now... More information you can find at http://support.microsoft.com/kb/935257/en-us