An interesting article has just been published by Ovum, “Skype helps “anytime, anywhere” learning”. Whilst it specifically refers to the use of Skype, there are other web conferencing systems available such as BigBlueButton. This is an open source software system that is installed by JC-J.IN on a server that can be anywhere in the world. By carefully selecting the geographical location of the BigBlueButton server, latency is minimised for your target audience. This is especially so if both the presenter and the audience are in the same geographical region.
Here is the article by Ovum: Skype helps “anytime, anywhere” learning