Bungie had a pretty cool talk about their hair production pipeline and tools at the last Siggraph, and they've finally put up their slides for it:http://advances.realtimerendering.com/destiny/siggraph2014/heads/index.html
It's worth a look for anyone interested in trying to speed up hair production. The powerpoint file contains a few videos and more annotations than the PDF.
I wasn't able to read the videos directly in the powerpoint for some reason, I had to extract them (with 7zip), the first 4 show off the hair tools and are worth checking out I think.
EDIT: Also lots of stuff on their character assembling tool, shaders, and more, in the 250+ pages available here: