Thanks in large part to the growth of mobile and several key industry players, pay per call marketing is growing at a pace that is exciting for anyone involved in the industry.

One of the contributing innovators has been Ring Revenue, with their call-tracking platform for affiliate networks. Ring Revenue’s initiative has been responsible for introducing pay per call to tens of thousands of businesses, making them aware of the availability of this performance based ad model.

Marchex also stands at the top of the heap for their persistent promotion of the pay per call space. They are fervent believers in the industry with millions invested in its future. Their recent purchase of free411 is just one of many investments they have made.

AT&T is the grandfather of pay per call, having acquired Ingenio’s self-serve platform. With their multitude of local reps, AT&T is pushing pay per call harder than ever to gobble up the emerging market share. Up until the past year or two, they appeared to be using pay per call only to rescue advertisers who were dropping out of the monthly fee based yellow page advertising. But their interactive department now appears to be firmly behind the growth of pay per call.

And let’s not forget Google. Their click to call ad extensions feature has enabled them to convert their clicks into calls on mobile devices and finally monetize the pay per call model. You may or may not recall that Google’s first initiative into pay per call fizzled about five years ago. But that’s all behind us now. Today Google probably facilitates more pay per call phone calls than all the other players combined.

Despite the gains behind us, as Forester’s industry report points out (commissioned by Marchex), mobile is the rising star behind the upcoming growth of the pay per call industry. Forester predicts the pay per call industry will be worth 6 billion dollars in annual sales by 2014 (two short years!).