How many conference calls have you been on where the discussion is so off topic the most productive use of your time is playing solitaire?
Having done conference calls for 20 years and webinars the last four or five, I can say that the visual prompting of the webinar improves attention.
The last couple of years we’ve done a number of conference calls using Netspoke, which allowed the call leader to share his desktop with everyone via the Web (still using standard conference calling for audio).
My problem with Netspoke is it is relatively pricey. Especially if you only want to use it occasionally.
An alternative is Vyew ( http://www.vyew.com). It’s free (with a small ad in the upper right corner) or very inexpensive.
It is a bit more complex for attendees to log in (you have to make sure you have flash and java installed in your Web browser).
It appears to be more stable for Mac users.
Did I mention it’sfree? Pay attention!