How to use Google Talk voice and video calling on an Android? How do you do Google talk voice and video calling from android.

The google talk application only appears to allow text based chatting. But Google talk on the desktop supports both voice calling and video chat.
There is no official Google talk voice/video chat for Android phones. You can use Google Talk in Android 2.3.4+ to make video chats now. Additionally, any calls made via Google Voice are done via cell tower (using your minutes), not data.