I'm not putting myself forward to port this, but:
Android is great, but it has a lot of proprietary software on it (the UI, Drivers etc.). So, some people decided to get rid of said software, and replace it with free software, creating Replicant. Replicant is also great, but no version so far includes 3D H/W acceleration. With the details of the VC4 now available, the Pi could be the first.
Replicant page here: http://replicant.us/