Analysts often talk about predictions and trends in the marketplace. It seems except for voice, everything is on the rise: Cloud, VoIP, SAAS, mobile, social media and, yes, even conferencing.
What is driving conferencing?
The economy has something to do with it. Conferencing saves on travel and makes the sales process more productive. With more remote workers, it's one way for businesses to remain in touch with all of their employees for training, information, policies, and of course project collaboration.
Add in that there are a number of competitors in the marketplace - Skype, Vidyo, MegaMeeting, Microsoft Lync, Lotus Live, PGi, InterCall, and the Conference Group just name a few - and that probably means that the conferencing pie is large and growing (or it couldn't sustain this many vendors.