The best feature of today's on-line meeting services like WebEx or Placeware (now Microsoft Live Meeting) is the shared whiteboard. Despite the limited drawing tools these services provide an excellent compensation for the phone's 100 year old limitation of being voice only. On-line shared sketches -- collabodrawing -- may provide the missing eyes and shared visual that truly strengthens complex communication. Many of Web meetings includes decent live video of the speaker too!
With one-click meeting creation it becomes exquisitely simple to add the interactive whiteboard to any live phone conversation -- be that traditional or as VoIP through many of the new super tools like Skype. The whiteboard not only allows for increased collaboration -- true e-Presence -- it also provides an effective capture mechanism for saving important sketches and diagrams. Anything pasted, drawn or otherwise shared may be wrapped in metadata, saved, searched and printed for later reference.
Today roughly 6-10 of my meetings in any given week are entirely Web-based. More importantly more than 90% of all phone calls lasting more than 8 minutes are now being supplemented by an on-line whiteboard as well. Visual is just one click away -- and it does add to an e-ffective presence.