Just noticed adsense are testing a 7 ads per box option in their wide skyscraper mode on Site Meter stats pages. Not sure whether I like it or not though - font is quite small. I've noticed they struggle to fill my two ads per page quite often so I'm not sure how they'd fill two if one of them had 7 ads in it. Have posted a little post about this here with a picture of the new format in case they take it down.
the font IS really small. And nothing cries "i am of possible interest to you" than big bright letters.
Yes, that's probably it. I noticed it yesterday and it doesn't appeal to me at all. But maybe they're testing things out.
Sitemeter is a test site - they quite often have new formats on there. I've noticed that some of the things they test make it to the rest of us (ie I first saw two ads per page there and image ads there - but I've also seen quite a few things there that have never made it to the rest of us). So no its not available to all and it may never be. Guess it depends how it goes in testing.
It looks like a premium publisher adsense block (Note the lack of Google advertising on the page). It's not something that the average user could use.