The physical Google button is a somewhat terrible idea, I think someone tried something similar a while back http://bit.ly/1rZkPdO
The idea is the same as Google's Voice Search (and Siri).
http://www.google.com/insidesearch/features/voicesearch/
The physical Google button is a somewhat terrible idea, I think someone tried something similar a while back http://bit.ly/1rZkPdO