Oh at the minute i think they are great! It's a good deal for all - but the next level is 3 blocks on a page..... Then what? I just think like everything they will go to far.
Soon i'll be visiting pages that have 3 pop ups/unders - 3 adsense blocks, 3 banners, 30 text links .......
Wheres the actual content? Alright i'm a pessimist.