No QAM Loving Before Christmas In Vista
I am quite surprised at how big the TGB is now! WOW! At any rate, I came across a thread from a Microsoft rep saying there will not be native QAM support before Christmas. As mentioned in the TGB thread linked below, you are more likely to see QAM support with a major update of Media Center. When will that be? I have no idea! However, there are work arounds in Vista. HDHomeRun and Avermedia both have plugins that allow for QAM tuning.
If you are looking for true native support you will have to look at SageTV right now as they are the only software that has native support for a few cards out there.