As expected, Google has finally announced the details of its wireless smartphone service that will, at least at first, piggyback on the networks of Sprint and T-Mobile. It’s called Project Fi and plans with unlimited talk/text, unlimited international texting, and WiFi tethering will start at $30/month, with each gigabyte of data you use costing an additional $10. And if you don’t use your full allotment, your account gets credited accordingly. [More]