CPA stands for “Cost Per Action”.
Its a relatively new and emerging trend in SEO services.
CPA is the rate of return (the amount you get paid as an advertiser) for when a visitor from your website performs some action. These actions could include buying a product or service, signing up for a newsletter, transactions including leads such as the receipt of an e-mail or phone calls originating from the Web site.
I’ve heard the Instant Money Code has a element of CPA which is exciting as 2010 is certain to be the year for CPA promoting.