Wainhouse Research released their latest predictions for the state of the global conferencing market. They forecast global conferencing services to grow at a 5% compound annual growth rate (CAGR), exceeding $US 4.5 billion in 2010. They say that web conferencing should lead the growth curve at an 11% rate, while video bridging will drop by more than 8%.
Note that these figures are for associated services... not sales of endpoint products and technologies.
The full three-volume set of research around the conferencing industry is available from the Wainhouse Research website.