I've been running 4.2 on my Galaxy Nexus for the past few days and I'm kind of disappointed. For one, the new lockscreen is awful. It looks ugly and is a mess to use. It feels like it was rushed. The new clock, though they finally added the timer and stopwatch functions from AOSP, is hideous and frustrating to use. It's red and gray. Where did the red come from? It's the only stock app that's primarily red instead of blue. It feels out of place.
Other than that, 4.2 is nice. I love gesture typing. It works much better than Swype and now I don't have to go through the PITA process of installing Swype every time I flash a new rom. The new camera and icon are nice, and photo sphere is cool. And the GNex seems to take slightly better pictures. The camera focuses a lot better. And it's about time they added something like quick settings, which works great.
So what are your thoughts on 4.2?