Google recently annouced and invited webmasters to test a Cost Per Action AdSense program - basically, allowing them to be paid on a “action oriented” basis vs. an clicks or impression oriented basis. Reactions on some sites were certainly mixed, but it looks like an interesting progression for AdSense (or as one commenter called it, “full-on-assult to the affiliate marketers“)

Of course, I’m intersted in the user side experience - what will the more CPA oriented ads look like (if you read some of the language included in the accompanying posts, it appears Google is pushing a different type of ad for its CPA participants) and how much response they get from consumers.