This week, forums and blogs were all a-buzz trying to make sense of a letter that Google sent to a number of Adsense publishers. In short, the letter politely informed them that Google disapproved of their “business model” and would be terminating their Adsense accounts effective June 1. (Publishers would still be paid for earnings up until that date).

It appears that all these publishers (in a wide range of earnings brackets) were doing arbitrage – using paid advertising to send traffic to a page where visitors would click on Adsense ads. This is puzzling because Google has stated in the past that they respect arbitrage as a business model and has brought up speculation that the publishers are also being targeted more for landing page quality and visitor experience (i.e. “MFA” – Made for Adsense – sites) and/or low advertiser conversion rates than for the manner in which they drive traffic. An interesting look at those possibilities here.

So far, no official statement from Google, and it remains to be seen how removal of these accounts will affect other Adsense publishers. Cleaning up the content network may, in the long run, turn out to be a win-win situation for all. Stay tuned!