robertdjung - 6:47 am on Jun 22, 2006 (gmt 0)

yes, but how long will it take for G to figure out when Cpa will work vs CPC. will it cost me $20 in lost revenue for each new advertiser? $10, $5? How much in lost earnings while each ad is "tested" on my publishing space?

And that's the problem. if they're going to test, then the savvy marketer will simply churn their ads constantly so none convert well ... if they're running a model where online sales conversions are the point. (800 numbers, branding, directions to business...)