I just read that Google is requiring a 3 year commitment on the hardware.
The $28 per user monthly subscription fee will be covering hardware, a web console for multiple users, warranty and replacements, support and hardware auto-updates. Google tells Search Engine Land that there will be a three year subscription required and hardware will be upgraded at the end of the three years, if companies continue the service.
That is a pretty long commitment for an unproven product. I would have liked to see a month-to-month commitment, quit at any time. That would make me feel like they really believe in their product.