On the last day of January an Android 4.0.4 Ice Cream Sandwich build number IMM26 for the CDMA version of Nexus S 4G leaked out which more or less paved the way to the official rollout of a software update canceled in early last month due to some issues found in the 4.0.3 version.
Yesterday a leaked screenshot of a document from Sprint’s internal system points to February 16 (today) as the day when the next wave of software updates should start rolling out to Nexus S 4G devices (that’s today). So by the time you wake up this morning a new firmware might be waiting for you to download.
If you’re on Sprint and you havent receive any notification to upgrade your device yet, try checking manually to see if there is an update waiting for you to download. AndroidPolice says their anonymous tipster tipped them in the past which makes it a reliable source now.