I was just on my web design website where I have an 468X60 adsense advertisement. It's text only format, but in the bottom left hand corner I saw < > and I was able to keep browsing through loads of advertisements like it was one of those top stories where can click 1, 2, 3, is this new? It's the first time I've seen it on google adsense.
I saw them on my site a few weeks ago and emailed them cuz I was scared to touch them for fear of setting off some invalid click alarm. They said they enabled them on only a few sites at first, not sure how far they are in implementing them now though...
I hate those <> things on my site ads because of fear of invalid clicks by someone who just might get click happy wondering what those <> things really mean. There is no explanation of what they really are, although I know it means "see more ads like this" or something to that affect. Oh well, I'll learn to live with it I suppose.