As part of my role here at Microsoft, I spend a significant amount of time in LiveMeeting doing presentations to Gold Partners. Sometimes it is a small meeting with only a few attendees, and sometimes the meetings involve hundreds of Partners at a time. LiveMeeting scales very well for both scenarios, and the experience on both sides (presenter and attendee) is usually quite nice. The audio portion of the session can be conducted via an audio conferencing bridge, or via "Internet Audio Broadcasting" where LiveMeeting dials into the Phone Bridge and then broadcasts the audio to attendees so that they can listen with their computer speakers. This is really the preferred method once you have a large number of attendees, as you will INVARIABLY have several folks that don't remember to keep their phone on mute (or that puts the entire conference on hold), which really ruins the experience for all involved. With that in mind, the following are some Best Practices that I use when preparing for and giving my presentations:
You will of course have to modify the above rule to fit your specific scenario, but do not enter the trap of giving a presentation with 100 slides and 16 point font. It will put your audience to sleep and force you to read from your slides, which is the cardinal sin of presenting!