HD titles will only be available on tv (directly) for rent, at least for now… If you purchase a movie, it’ll be in SD (typically widescreen). No doubt Apple set it up this way to placate the content providers (studios) on the piracy front. The studios want a fail-safe method of protecting HD content. So, it cannot be moved around like SD can. Remember, iPod’s can’t deal with HD anyway, and arguably neither can the iTunes host (i.e., there is no high-def norm for the host, and it just doesn’t meet the Apple simplicity standard). This may change eventually, but that the way it is right now.