Well, some of them.

It’s been reported that Google have been closing numerous Adsense accounts, and some people have been speculating it’s due to a new crackdown on arbitrage tactics. Without a copy of the email, it’s difficult to know for sure.

From WebmasterWorld:

� know of two associates who were doing arbitrage and yes they got the same email on the 15th…..their accounts will be disabled June 1st. These guys were sending adwords traffic to their landing pages. From what I saw their landing pages had good content but were a MFA site with two blocks of adsense code at the top and one at the bottom. No other external links on the page�.

Somehow, I doubt it’s due to arbitrage. It’s more likely due to non-performance, from the advertisers point-of-view.

Arbitrage can provide value - there are examples all over the web, and offline. Advertising buys, local search, affiliate, e-bay stores, and, yes - major search engines - all use arbitrage, to a degree. Arbitrage is a given in any inefficient marketplace - which is all of them.

As far as Adsense goes, it will come down to how the arbitrage is implemented. If there is no value provided to the advertiser, expect to get canned by Google eventually, arbitrage or otherwise. Google have made no secret of the fact that their philosophy orients around providing utility to the end-user, and that includes PPC advertisers. Many made-for-adsense sites provide no utility whatsoever.

So, less to do with arbitrage. More to do with publishing page-after-page of nothing but Adsense, methinks.