Sorry for the acronym...
HLS stands for Http Live Streaming. It is a streaming protocol submitted by Apple to the IETF (Internet Engineering Task Force) and is gaining a lot of traction.
Roku will be sharing more information about our implementation very soon.
HLS deals with the prebuffer issue in the sense that an m3u8 file can list other m3u8 files that list ~10sec intervals of transport streams.
A playlist could be implemented in HLS as a master m3u8 file that lists other m3u8 files for each video in the playlist. Because the video m3u8 files list transport streams that are segmented on I-frame boundries, our HLS player can prebuffer them and seamlessly transition to the next transport stream when the player is ready.
So yes, HLS will enable playlist support and address the prebuffer issue.
If you want to start learning more about HLS and m3u8 files, the following resources may be of interest:
http://developer.apple.com/iphone/libra ... ction.htmlhttp://tools.ietf.org/html/draft-pantos ... reaming-02--Kevin.