Early on, I was definitely a proponent for hg over git. I assumed it would at the very least remain a peer, given how much more sane the UX is. I was wrong though, and I don't think it's just because of github.

Named branches being baked in turned out to actually be a real pain in mercurial. Sure, you can use bookmarks (and we did) but starts to quickly feel like you're swimming against the current.