Well, back in October, there was mention of Google "confirming" that the Nexus S would be getting ICS "within weeks." They weren't clear if that meant within weeks of that statement, or within weeks of the Galaxy Nexus launch. I'd expect the latter.
Since the Galaxy Nexus has launched in Europe, that could mean we'll see ICS for the Nexus S as soon as early December, but considering the Verizon version may not even have launched by then, it could be as late as January when the NS finally gets ICS.
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