After reading a recent online interview with CNET and Andy Rubin I now have a better understanding of Google's persistence with a mobile OS. Since Google aggregates, sorts, and serves up the data we are looking for on the WWW they are seeing themselves as the de facto gatekeeper of information.
Google's Android is a mobile enabler of information. If/when we cannot access information via traditional means of WiFi, wired, desktop,or otherwise then Android will be there for us on many mobile devices.
Since Android is free to OEM's and developers then it can be customized for many form factors as well. This is where the tipping point of Android will be, when the software dominates hardware development and the user is considered primary.