Today I'm going to be doing more testing of online conferencing environments -- today's test subject is Sametime, a conferencing and collaboration tool developed by IBM/Lotus Notes. From what I've seen, it's coming down to a choice between Centra, Interwise and Sametime.
Each product has its strengths. The true test of each will be how well it supports the synchronous, instructor-led online training sessions.
Another key feature will be an ability to "serve up" preliminary asynchronous content (prerequisites) prior to instructor-led sessions.