Gizmo rolled out a new flash-based application “GizmoCall” that lets you make calls to other Gizmo users or to telephones using your web browser. Like Skype, you pay really low rates for calls to landline / mobile phones, while PC calls are free. GizmoCall supports video calls as well, and it can turn any phone number into a link, like this test number.
Gizmo has opened up its APIs for developers to add calling features to their apps compare to the APIs from Ribbit or Ringful). GizmoCall phones are also embeddable to your homepage, blog, or other web site. Gizmo also offers a desktop client for Windows, Mac, Linux, or Nokia Tablet users. And there's a mobile version that runs on a variety of cellphones including BlackBerry and Windows Mobile devices.