Okay, so I got my Galaxy Nexus yesterday, and spent pretty much the entire day setting it up and tweaking it to my liking. Today, I had my first day of actual use, and I think it did pretty well.
First and foremost, the battery life held up pretty well. I keep 4G on, use auto-brightness, turn off syncing (I'm perfectly fine with apps updating when I open them), and also use Juice Defender Ultimate. I had the phone off the charger for about six hours, with 20-30 minutes of web browsing, e-mail, etc. By the end of that six hours, I was only down to 90%. Pretty much the same kind of battery life I was getting out of my rooted Thunderbolt, so I can't complain. There will be days when my actual usage is a bit higher, but I suspect battery life will still hold up pretty well.
The stock launcher is pretty solid. I don't mind the permanent search bar, nor do I mind the lack of a scrolling dock. The only thing that kind of irks me is that folders limit the amount of items you can put in there. I suppose I've been spoiled by Go Launcher and their much higher folder size. I have tons of games, and I was hoping to make one "games" folder with all of them in it, but now I have to make a "Games 1", "Games 2", etc. setup. I also wish they'd allow you to use custom icons for apps, but I guess I can understand why they wouldn't allow that in stock.
Thus far, I haven't made or received any calls, so I don't know how well that works. I also haven't done much to use the speaker to have a valid opinion on that.
My biggest negative is the amount of trouble I'm having with connecting it to my computer to transfer media files to it. I managed to transfer over 50+ custom ringtones, but every time I try to transfer pictures to the appropriate folder, the transfer process just hangs and crashes my Windows Explorer. I did manage to also get 200+ wallpapers transferred over fine, but I can't seem to get my pictures from my old Thunderbolt to copy over to my Pictures folder on my Nexus.
One thing that has surprised me is that wifi seems to be much faster on my Nexus than it was on my Thunderbolt. I don't quite understand why that seems to be the case, though. For instance, I have a selection of songs in Google Music downloading to my phone over wifi (about two gigs worth). When I did this on my Thunderbolt, the download took over six hours. On my Nexus, it's only taken about half that.