Rub your hands in glee, cinophiles, for Apple has released a public preview of QuickTime 7 that includes support for high definition video and up to 7.1 audio!
It has a cleaner interface (looking more like iTunes every day), a better laid out settings window, improved playback controls and H.264 codec high-quality video support, but for the average QuickTime user who likes to watch streaming movie trailers or short films online, you won't really notice too much difference. The Pro version, for an extra $US30, gives you a few more bells and whistles that include the ability to create your own high-definition movies with surround sound, save (and trim) online content, and fullscreen mode - these last two being reason enough to purchase if you want to watch streaming content more than once.
Apple QuickTime 7 for Windows
Price: Free (basic version); $US30 (pro version)