A late Monday tweet from the handset maker advises that the update is rolling out in phases. As is the case with other Android 4.0 builds, the Droid 4 will get features such as face unlock, data management, and a friendlier user interface.
It's not immediately clear how long it will be before all handsets receive their update, but in my experience it typically only takes around a week for full deployment. It's possible in some cases that consumers can manually push the update through by checking their device settings, although I've yet to see any confirmations of this tactic proving successful. Motorola has also posted a Web site dedicated to the Android 4.0 update for consumers who would like to learn more about the benefits of Ice Cream Sandwich.