Got my Pixel XL last night. Really enjoying it so far. It is smaller than my N6 by quite a bit, but feels good in my hands and is fast. It's at that point where it just works and you aren't thinking about any slow downs or lags in the UI.
Battery life is has been good so far, but of the 21+ hours I had on the initial 85% charge (directly after opening the box I got it in), part of them were while I was sleeping which had little to no battery usage. It was almost exactly flat, which is quite awesome. Also over 6 hours screen on time, which is pretty damn good.
Google Assistant is a beefed up Google Now, but more conversational. It will sing you short songs and cringe worthy dad jokes. I love it just because of how much it annoys @Chimera, the look she gives me every time I have it sing something or tell a joke is great.
I'm glad I got it so far, will report if there are any issues or interesting things to note.