Apple today announced that with iTunes 8.0, HD TV shows are now available on the iTunes Store, including content from longtime holdout NBC/Universal. The new HD offerings are priced at $2.99 per episode, or $1 more than the SD versions of the same shows, and can be viewed through iTunes on a computer or from the Apple TV. Content from NBC includes the popular shows “Heroes,” “The Office,” “Battlestar Galactica,”…