I haven't seen many businesses saying "Skype us!" I tried putting my Skype link on craigslist for awhile, but phone calls/texts always heavily outnumbered it.
I wonder what percentage of usernames are primarily for spam vs personal vs internal/B2B business conferencing.
You're right, but I've seen many sites where there is no telephone number. The only methods of contact are e-mail and Skype. In that case, Skype is usually preferred by me because I can get an instant response usually.