My Yellow Pages is going to kick your phone's butt
No press release yet on either site as far as I can see, but France Telecom's directories business, Pages Jaunes, has teamed up with eStara to deploy its web-based click-to-call functionality eventually across its entire advertiser base, which apparently includes 327k sites!
UPDATE: A mega-uber value reader in the Netherlands pings me to point out that online directory De Telefoongids already offers a similar service. Have a look at this link to a search query I did earlier today - for KPN's competitor Versatel. About halfway down the page, next to the third result, you should see the phrase "bel gratis" ("call free") in red, with the KPN logo next to it. Click it, and you will see that you have to enter your fixed line phone number, which means that this is basically a call-back service, I assume based on SS7, similar to what Web.de launched about four years ago in Germany (albeit that was a consumer subscription calling model). In this case it is apparent that KPN must be eating the cost of the call, even though the company does not own De Telefoongids (and even though the call is to a competitor!). In the case of Pages Jaunes' service, the description in the release seems to suggest that it is capable of being used either as a ring-back service like this one, or as eStara's conventional click-to-call-direct-from-the-site model.