Video Conferencing is one of the coolest features built-in to Office Communications Server 2007 R2. It is extremely simple to use from an end-user perspective. Just plug-in any off the shelf webcam, and both Communicator and Live Meeting immediately recognize it.
Here is a screen shot of John Santiago (Catapult) and me talking over an internet connection. John was at a customer site and we were actually demoing this capability. Video conferencing makes meetings pretty fun too because you can see facial expressions and body language.I selfishly like it because it saved me a flight to Denver for this particular meeting =) !!
Video conferencing is not new, but what is new is the ease that a Video conference can be launched due to the tight integration with Communicator and Live Meeting. You can add video to an existing audio conversation on the fly with a single mouse click. Also, the bandwidth is pretty efficient too.
Here is a screenshot of a bandwidth monitor (see my blog post about this tool here) that shows the bandwidth usage.