"Google tests a new feature that makes Gmail chat more useful: users are able to make and receive Google Voice calls from Gmail. A new phone icon opens a Gmail chat window with a dialpad, an option to find contacts, a credit balance and a call button.Continue reading : Google Voice to Integrate with Gmail as a VoIP Service
Right now, if you want to call someone using Google Voice, you need a phone. You can either visit Google Phone's site on your computer, enter the phone number you want to call and wait until Google calls your phone and connects you for free or use Google Phone app on a mobile phone."
Posted @ Google Operating System