Interesting ... I'm on Slow ring at the moment ... fast ring means it's a bit more bleeding edge.
I'd guess something similar should hit the slow ring a bit later.
There were also some theme hacks doing the rounds to bring back the bar colourization that WAS there in earlier builds.
PS. I may keep my dual boot on Insider slow, but before the year is up, I'll have to upgrade and then restore my Win7 so I can lock in a non-Insider licence