Amazon adopts eStara’s click-to-call functionality (written up in today’s WSJ [sub. req’d]). The article confuses "click-to-call" and "pay-per-phone-call" (one is infrastructure; the other is revenue model).
eBay has begun to do the same thing in Europe with Skype.
Click-to-call facilitates buyer-seller interaction or can drive leads, which can potentially be monetized on a per-call billing model (PPCall). Regardless of whether calls are individually monetized, click-to-call provides additional value through tracking of the relationship between the Internet and the ultimate offline transaction.