Apple will soon release its long-awaited "Tiger" version of OS X (10.4). Included in this release are significant enhancements to its iChat voice/video application including the ability to create audio conferences for up to ten participants. A quicktime demo is avalable at: https://www.apple.com/macosx/tiger/ichat.html
Perhaps the "coolest" feature in the new iChat AV is a desktop video conferencing feature that allows you to create a "virtual meeting" with up to four participants. Video is crystal clear thanks to the H.264/MPEG-4 codec. Rather than just video boxes on the screen, video conference participants appear to be seated around a virtual conference room table, complete with reflections of the participants in the table as shown below.
With this release of iChat Apple brings the ability for voice and video conferences to easily be created on an ad-hoc basis by any individual. This has got to be a network manager's worst nightmare given the potential bandwidth usage of video conferencing (specs are not yet available). However, it give us all a glimpse into the future, where centralized services aren't necessary for rich-media communications and collaboration.