AdSense publishers will notice a new tab when they log into their accounts next – ‘Site Diagnostics’.
It seems that this new tool highlights any pages that AdSense is having problems running ads on.
There are a number of reasons why ads might be having problems that are listed at their help page – Why is my URL showing up as blocked?
I’m not seeing any blocked pages come up yet for me but have heard from a number of AdSense publishers who are telling me that this new diagnostics tool has already identified problems that they were not aware of.
There’s no announcement yet on any official AdSense pages apart from that help page with more information but at a first glance it looks like it could be helpful.
Update: It looks like this feature was either launched by mistake too early, or they are having problems with it because most peole are not seeing it any more. Very odd.