Am I missing something? I thought that movies are now available for rent in HD on Macs, directly from the ITMS. It looks like some are, but most still say, "also available in HD on Apple TV." For example, it looks like Twilight is available for rent in HD on the ITMS, but that Dark Knight says "also available in HD on Apple TV." Is there some sort of transition period we have to go through before the full HD library is available?