For those lucky enough to have both an Apple TV and an iPhone or iPad, the potential and power of AirPlay has been enticing. Start playing a video on your iPad and finish on the big screen in your living room? Share your YouTube clips or movies with friends and family in comfort? Start video or audio playback from iTunes, while using the Apple TV as an endpoint? Yes, please!
While the first edition of AirPlay was reasonably capable (and souped up noticeably by some clever developers), it has operated under some limitations. No third-party apps had official access to the video APIs for sharing streams, and Apple only supported video from the Videos and YouTube apps; even the iPhone's camera roll videos weren't streamable. Now, with iOS 4.3, most of those limitations are gone.
4.3's AirPlay allows playback of videos straight from the iPhone's Camera Roll, meaning that your snapshots and quick clips can be shared immediately. Websites that show H.264 video in Safari can stream to Apple TV as well, which is sure to be useful. Third-party app support is there too, and though it may take a little while for the developer community to catch up, the possibilities are vast and very cool (Hulu, anyone?).
In addition to the wireless streaming magic of AirPlay, wired video playback gets a boost with iOS 4.3. The new version allows for "720p HD video playback from the Videos app, iPod app, Photos, YouTube, Safari, Keynote, and enabled third-party apps on an HDMI display," meaning that you'll need one of Apple's new Digital Adapters to make the magic.