A member on Webmasterworld noticed a new Adsense format being tested on some sites. A number of members confirmed seeing this new format as well. Here's a sample image :

I think that there are a number of advantages to this format :

• It adds interactivity to the ads; I believe visitors are more likely to click on an ad if they can interact with it.
• The abillity to scroll means that more ads (variety) can be displayed withing a limited space.
• This should allow for more opportunity for targetted ads to be displayed.
• If this format is applied to Referrals 2.0, then there is a possibility of more clicks (higher CTR).

I haven't seen it (this format) appearing on my sites as yet, but I think I have on other websites. Whether publishers like the format or not, one thing is clear (to me at least) - Google is pro-active and changing to meet the problems of ad blindness, in particular, Adsense blindness.