According to TechCrunch some Nexus S owners are reporting various problems with their phones after applying the ICS update. These problems include loss of wireless signal and rapid battery drain. Google is "monitoring the feedback" to determine when to resume the update rollout to the Nexus S.
See also: The flawed Android update process; too many cooks
The problem with this update demonstrate how hard it is to get an update out for Android devices. The Nexus S is not new hardware, it is the Google flagship phone that preceded the Galaxy Nexus now shipping with ICS. Google has already updated the Nexus S from early Gingerbread to the current version of it, and is now tanking on the ICS update.
Face it, Google knows this hardware backwards and forwards, so if it can't get the ICS update working on the first try what chance do OEMs have? Remember, the Nexus S update comes directly from Google, not Samsung or some carrier. It is Google's phone, Google's OS, and Google's update process that is failing.
Those of us who own the Sprint version of this phone, the Nexus S 4G, are waiting in the wings for our own ICS update. Perhaps we are the lucky ones, letting the other guys sort out the bugs first. Although, even though Google is having trouble getting this ICS update to work, the homebrew community figured it out just fine. I am still enjoying ICS on my Nexus S 4G, and without problems.
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