Here are two screen shots taken in-world at two meetings I attended recently in Second Life.
These are legitimate meetings that are being held in virtual space with people from around the globe. This technology is still in its infancy, but holds great potential. This is mainly due to the fact that the price of admission is a computer able to run the Second Life client software, and not a full blown video conferencing setup.
The Alternate Reality Games meeting included voice and was broadcast to the Internet. There were a few glitches with the sound, but again, we are just seeing the early attempts at this sort of thing. As we move forward these experiences will be more immersive, and of better quality.