Google announced last week that it had begun rolling out an Android 4.0.4 upgrade to certain models of the Nexus S and Galaxy Nexus along with the Wi-Fi variant of the Motorola Xoom. Such large-scale updates usually come in waves, and Android Community reports that the Xoom Wi-Fi OTA update is now being received by users. The new version of Ice Cream Sandwich is said to bring along with it smoother screen rotation and camera improvements, amongst other tweaks. If the update notification hasn't popped up for you yet, you can manually poll for it in the Settings app — but unfortunately there's still no word on when 3G or LTE variants of the device will be getting their updates.