Unfortunately, things didn’t go that great on the Nexus S and Google discontinued the update, leaving many phones with Gingerbread, and others with a somewhat poor ICS experience.
All that should be fixed with the latest ICS build: 4.0.4.
In this build, which is rolling out to Galaxy Nexus, Nexus S, and Motorola XOOM devices, screen rotation is improved, the multi-task feature is much faster, and various improvements have been made to the camera app. Most changes are behind the scenes: you’ll miss them if you’re not specifically looking for them. All in all, 4.0.4 makes Android ICS a much smoother experience all around.