HD streaming works on both Macs and PCs, though the library of HD titles is much smaller than the one available for the supported consumer electronics devices. You can check out a list of movies that work in HD on the Xbox 360 et al, but there's no list for browser-based player HD support yet, so it'll take some trial and error to find what you want.
Netflix hasn't made any public announcements about this feature yet, but we're hoping that the entire HD-encoded library will become available on the web. It's been a long time coming; user content-oriented sites like YouTube and Vimeo have streamed in HD for months, while pro content sites like Hulu and Netflix have stuck to standard definition.
We'd guess that most folks would want HD for Francis Ford Coppola films and Lost episodes more than they would want it for video blogs and cat vids. Then again, it's hard to argue with those crazy-popular Lady Gaga HD music videos.
