Unfortunately, the current plan is to prevent movies from being shown in high definition on most current HDTV sets, and forbid the creation of convertor boxes that would allow high-definition viewing on them.
So owners of most current high-definition sets will have ZERO reason to want to switch.
My understanding of the current plan is that Congress will pass a law for a "broadcast flag" to be used on some HDTV broadcasts. It would not forbid the broadcasting of movies in HD, but it would selectively restrict the ability to record those movies.