Google Talk Labs Edition is one of the new Google Talk flavors introduced by Google recently. It is a stand-alone application just like Google Talk Desktop and brings some of the features of Google Talk Gadget (emoticons, group chat etc) to the desktop along with fancy desktop alerts and notifications from Google online services.
Google Talk Labs Edition has built-in integration with Orkut, Google Calendar and Gmail and displays notification alerts from these services on the fly.
It would have been more better if Google directly added these new features to Google Talk Desktop through an update instead of launching a whole new separate Google Talk version.
Google Talk Labs Edition is basically a stand-alone web application and is powered by Adobe Flash. Even though it does not run in a browser you will still need Adobe Flash on your machine in order to run this application.