Vista - WLPG vs. WPG Thumbs?

I have a camera that takes videos in H.264 .MOV format. This format is
supported by Windows Live Photo Gallery (as long as Quicktime is installed),
but NOT supported by Windows Photo Gallery. I keep my photos and videos on
a shared folder (a server that all our computers can access).

When I access a folder with WLPG, it updates the thumbs properly. When I
access the same folder with WPG from my computer, it sees the thumbs.
However, when I access the same folder from another computer with WPG, it
does not see the thumbs.

Captions, tags, and other information is updated. It's only the thumbnails
that is not.

Is this expected behavior? Ideally, I'd like to see Quicktime integration
in WPG (like WLPG) and it would be a non-issue. I understand we may get
H.264 and .MOV support in WMP12, which will probably be more tightly
integrated. Short of these wishes, I was sort of hoping that WPG and WLPG
would at least share the thumbnail cache so I could fool the system into
displaying the thumbnails for .MOV movies on my 'other' computers.

It is really amazing to me how much information a thumbnail can convey --
they are so critical to proper management of a media library.

Thanks in advance for any advice.