I work in bioinformatics and I can confirm that most biologists feel very uncomfortable in the idea of having to touch LaTeX. As a result, in our collaboration project, I'd have to survive with using Word+endnote. It's a fairly painful experience..
I've made some good experiences with Authorea, a paid online collaborative scientific writing tool, I think that one runs on top of Pandoc+git too, but it doesn't have full Word import support yet AFAIK
Edit: 0 mentions for Authorea in this entire discussion, I guess these guys need to do a bit more advertising :)