I bought AppGameKit for the HTML5 stuff, and typically it is still vapour ware (although it may be here soon). I think for app design, the lack of video playback is a major loss, as it stops AppGameKit being an app making language, and more just a games making language. For some simple apps it would be useful, especially if you can use youtube etc to use as a video repository.
I haven't played Angry Birds on a phone, but I would imagine the video still plays from within the game? Rather than swapping to a browser and then swapping back? If so playback support is still needed, regardless of where you retrieve the video.
Still until they have updated all currently supported devices with all the new commands, this is still low priority. In fact I think they need to improve the sound commands first also. Will we ever see ogg support for tier 1?