I really like this new feature. I can see exactly what ads are being shown on my sites and can block by clicking an ad I don't like.
I found that the ads being displayed are actually a lot more targeted than I thought. Sure, an out of the blue belly-fat ad here and there, but mostly spot on.
Do any of you use this new feature? I'm suprised I haven't heard more people talk about it on WebmasterWorld.