Well, I also have to disagree with the "piece of junk" sentiment here. From my experience VMC, while not perfect, is still very good. It has proved stable and handles all my TV needs.
Yep, some things need improving, but they are not ALL Microsoft's fault.
- Video Thumbnails - irritating that they show no title or have a list mode. One for MS to fix.
- Guide - No native support, but not Microsoft's fault. ALL HTPCs have the same issue there.
- AVI Support - Not native, but ffdshow works fine with VMC so not a major issue.
Aside from these I really haven't had much in the way of problems. I don't fiddle, leave the HTPC as a HTPC only and keep add ins to a minimum (I only have an internet radio add in and Webguide4).
Sure, there are a few setup things that newbies may trip over (such as the guide) but once set up, it is stable. I built one for my in-laws. They haven't had any major dramas since it went in (they've called me twice I think. Both times a reboot fixed it and I have advised them to reboot weekly, just to keep it "fresh").
I'm no MS fan-boy, but on the whole VMC is not a BAD product - it's just not perfect, but what is?