Craig,I've been travelling all week but picked this up as well. I plan on popping it in tonight!
It's interesting how the film grain varies depending on the shot. I don't remember if the Blu-ray was like that ( I might need to watch parts of it ). There are some really grainy / gritty scenes, and there are some very clear clean scenes. And, it looks totally appropriate to the scene itself. If the BR was like that, the 4K BR conveys it even better.