There is unclear speculation at WebmasterWorld that Google is placing the Google Checkout Icon it uses on AdWords ads also on AdSense ads.

For example, Dicks Sporting Goods uses Google Checkout and a search for a keyword they are bidding on has the special shopping cart icon on their AdWords ads. It looks like this:

Google AdWords Ad

After a few minutes of tracking down a site that had an AdSense ad for Dicks Sporting Good, I was unable to verify that Google is placing the checkout icon on the AdSense ads. Here is an ad I pulled from one site.

Google AdSense Ad

I was wondering if anyone has seen the icon on a contextual Google AdSense ad?

There is speculation at WebmasterWorld that this is a limited test.

Forum discussion at WebmasterWorld.