Well it’s something we’ve been expecting for some time now, and finally Google is launching Google Talk with video and voice chat for Android phones. However it’s not coming as a market update of the Google Talk application, at least not initially, but rather as part of the Android 2.3.4 over-the-air update for Nexus S devices. Devices should be updated over the next few weeks.
It should then launch to other Android 2.3+, i.e. Gingerbread and Honeycomb, devices in the future. The new feature will allow you to make video and voice chats from an Android phone to anyone running a compatible version of Google Talk either on their phone, tablet or computer. Calls can be made on 3G, 4G (provided that your carrier allows this) and over Wi-Fi.
[Google Mobile Blog]