Adobe Acrobat 8 has built-in Web Conferencing

Now this is interesting.  See http://www.adobe.com/products/acrobatpro/ where "Enable users of Adobe Reader® software (version 7.0 or 8) to participate in shared reviews.Use the Start Meeting button to collaborate in real-time with the new Adobe Acrobat Connect line of products." 

It is likely that users of Adobe have not yet experienced web conferencing, and using this "safe" option could be their introduction.

I'm not sure that all products need to have built-in web conferencing, but it's clear that only a very small minority of the world has yet to experience it.