I was browsing this interesting article on click-to-call or pay-per-call or whatever you want to call it. I have always thought that integrating the telephone and fax into the mix would be key to getting small and/or local businesses interested in online advertising as a means of lead generation. It lowers the barrier of having to have a web presence of some sort or to develop the ability to support e-commerce. My guess is that there are many small businesses who already understand how to close business on the phone, especially if the caller is in search of information to make a purchase decision.
My guess is that click-to-call will be a good way to get small businesses and local merchants on the web without requiring them to maintain a web presence. The interesting question, I think, is whether any of the major web properties will be able to take these CTC customers and upsell them to more traditional keyword advertising and expand their relationship with them. It could be a really huge opportunity to bring a lot of new advertisers to the Internet.