As a part of Android 2.3.4 rolling out in next few weeks for Google Nexus S and don’t know when for other 2.3.x Android devices (I hate Android fragmentation), Google Talk will be updated to support video and voice chat.

talk_videochat_update Talk videochat - buddylist

You cannot get this version of Google Talk from the Market and it will only be available in the firmware update. Anyone with earlier version of Android devices will be left out.

[via Google Mobile Blog]