Customers are reporting that the 4.1.2 update has made them happy.
Just received update 4.1.2 on my Nexus S – brilliant fixed the bug on making phone calls- so very happy. Kyren Tremble
The list is not very long. In fact, the list is pretty much non-existant as far as any features go. All those goodies will be saved up for Android and the next Nexus devices.