Certainly click-to-call has limitations and risks for abuse, but implemented correctly it can offer clear advantaged for certain web service providers.  Contrary to some reports, Google’s click-to-call was not pulled (it is still functioning).

Integrated into web based services such as Salesforce.com, Mailroom (woot!), Basecamp ~ our Podcall functionality can offer unique social interactions and services previously difficult to implement and afford.

Yesterday I had an interesting call from a prospective Podcall customer and a feature we had previously not announced came up.  While we provide the phone system, network interconnection and API hooks we don’t necessarily have to provide the minutes.  If you want to negotiate your own wholesale minute rate we can simply connect to your provider and let you pay them directly.  No need for us to markup the dial-tone costs.  (our pricing for North America is currently around 2.5 cents per minute)