An AT&T-3G version of the Samsung Nexus S has been rumored for a while now, but while poking around at Google's Android Open Source Project git repository I noticed one of the changes made for 2.3.3 centered around the requirement for a new radio -- and it differentiates between T-Mobile and AT&T. I'm no Googler, but that sure looks like we're seeing Gingerbread being built for the Nexus S with AT&T in mind.
The page has disappeared for a bit while writing this one up, but the magic of tabbed browsing saves the day in case it doesn't come back online soon. Have a peek after the break for the full page view. [Android Open Source Project]
Update: The page is live again at the source link, but we'll leave it after the break as well for our mobile viewers.