I love Ice Cream, not security flaws!
The new feature (read: 'gimmick') in Android's new Ice Cream Sandwich OS 4.0 is fundamentally flawed.
I'm reminded of when I watched a demo of the latest Lenovo tech (three years ago) called VeriFace Face Recognition. It was being demo'ed with the, then, newly release Windows 7 allowing you to log into your computer simply by letting the Windows log-in prompt scan your face and use basic facial recognition to authenticate you.
This was swiftly proven insecure by simply printing a full page photo of somebody's face and letting the software pull the the recognizable points from the artificial medium.
ICS is basically flawed and vulnerable of the same exact circumvention methods... and with the widely available personal images found via Google+, Flickr, Facebook, etc... a simple bypass can be had with a swift CTRL + P or digital representation of that person via mobile device.
Below is the simplest way I could demonstrate this flaw with a YouTube video by somebody else. 