Personally I like it. Installed it yesterday late at night and I got to play with it for like half a day. So far so good, very few things to complain about.
I like the promised almost stock feeling it gives. Fingerprint reader feels kinda faster, maybe? Battery also feels maybe a little bit better but can't say for sure. Don't know if it still will lag once it reaches around 20%,hopefully not. All in all feels a little faster than before.
I saw that music streaming cover art now acts as lock screen wallpaper, which I find VERY nice to have.
Also now there's a HDR mode for selfies. Haven't played around with it much but I think it can provide a subtle but nice effect.
FINALLY the power manager isn't killing stuff it shouldn't. Like for example on nougat I tried installing the pixel live wallpapers and I tried every way possible to apply them but power manager always killed the wallpaper "app". Couldn't do anything about it either cuz it's not actually an app, more like a bundle of sorts, so it doesn't have an UI, and therefore it didn't appear on power manager.
Now to the complaints.
1. What is with the persistent carrier label in the status bar??? I see no reason whatsoever to have it there all the time. The notification icons look totally weird next to it.
2. Was kinda disappointed that camera2 API was not fully supported. Was kinda expecting it since so many people wanted it. Also the camera app in itself feels somehow weird? Maybe it's just me.
3. Daydream is temporarily not supported, at least so it said in the update description. Hopefully with another small update they add support for it and full camera2 API.
4. The app switching UI feels also weird and has a design like it was made with and for Windows 95. Not cool.
5. Also expected to have some fingerprint reader gestures available. Didn't deliver.
6. Also I saw that on video setting the stabilisation toggle is still backwards. How difficult is it to get it right?
I think that's about it, maybe? Like I said, all in all good, but still has some small stuff that bothers (sometimes more than they should). Love to hear other opinions about other stuff you've noticed.