Updated mine yesterday via USB ... no problems at all with the download or install. Just takes time. (I did the maps a few weeks ago.)
I have found the last couple of OS installs look to be a two step affair, and the USB needs to remain in place until you get the screen that tells you to remove it. In other words, the first phase takes around 40 minutes or so, and at the end mine did a reboot plus a notification to do a key/power cycle. After that was complete, it starts the "Updating System Software" again for a few minutes, then pops up the "You can now remove the USB..." notification. If you take the USB out after the first reboot, thinking it's done, it actually starts all over again. Don't ask how I know this ...
The only thing "new" or different I might have seen was a green phone on the upper right corner when I was on a phone call. That may not be new ... but I don't remember seeing it before!! Certainly seems a bit snappier as well.
Ken