I recently had a chance to explore using Zoom (www.Zoom.us) and find it to be a very good alternative to WebEx, GoToMeeting and join.me. The Zoom tool for web conferencing is fast to load, has an excellent selection of annotation tools (a must for presenting demos over the web), nice white-boarding capabilities, plus some very nice video capabilities.
Zoom offers a range of other communication tools (for webinars, private collaboration rooms, video conferencing, etc.) as well. I don’t know how pricing compares with other tools.
Any additional comments or feedback on your experiences with Zoom would be appreciated!