Google has just launched a new Adwords feature that offers lots of useful applications for online marketers. It’s so slick, I am a little surprised it hasn’t received more press. In a nutshell, Google Adwords can now track and report not only how many people click on an ad, but how many people call based on an ad.

Yes, you’ve doubtless heard claims like this before, but this one seems pretty solid and pretty powerful as well. Here’s how it works.

Google Adwords  dynamically inserts a key telephone number (supplied by Google) into all places you specify on your landing pages or even your full website. Put another way, anyone who gets to your website via Adwords will see a Google-supplied phone number and everyone who gets to your website any other way will see your regular phone number. You can format the Google numbers to match your website look and feel, and the phone numbers will be dynamically supplied for up to 90 days.

While Google doesn’t mention B2B applications specifically, you can immediately see the benefits. Few B2B buyers click through from an ad and immediately place an order. More likely than not, there’s a phone call involved, and even then, the phone call might not happen immediately. With this new feature, it’s possible to measure and track this unique aspect of B2B buying which is well understood, but has been devilishly difficult to measure.