Google's 'Inside AdWords' blog has just announced the extension of their Pay-Per-Action beta test beyond the US, where it was first launched in March. This will be a new pricing model for Adwords advertisers who are using the Content network to choose, if they wish. Pay-per-action advertising (often known as CPA - cost per action or acquisition) allows advertisers to pay only for completed actions that have been defined (such as a lead, sale, or page view), after a visitor has clicked on the ad being shown on a publisher's site.

This is effectively like affiliate marketing and it may be a valuable option for some advertisers who have consistent conversions and know the value of these. With standard PPC campaigns, advertisers need to continuously monitor and tune their campaigns to meet their target CPA (cost-per-action). However, Google says that with pay-per-action campaigns, advertisers only need to set their desired cost-per-action and pay for completed actions to hit their CPA targets.

There is a gradual roll-out being planned, so that advertisers who currently use AdWords conversion tracking and receive more than 500 conversions in the past month will be invited to join the beta test. Eligible advertisers will receive an alert in their AdWords account informing them that they can now try the PPA beta if they wish.

This is certainly an interesting new development within Google's range of search advertising options and although there is no evidence of the success or otherwise from the initial trials over the past few months, it should be tested by advertisers when they have the opportunity.