There's a session from WWDC 2016 that talks about this - https://developer.apple.com/videos/play/wwdc2016/405/

The LTO part runs from 14:00 to 22:00. The streaming seems to only work in Safari (for Macs), but you can download the mp4s in HD (1.2 GB) or SD (300 MB).

They do a good job of describing how it works and why this is kind of a big deal.