rocco - 9:48 am on Mar 24, 2011 (gmt 0)
Did you try to update the ads with a new code?
Do you run google maps?
Did you try to look at your website with other browsers?
I have a problem on one site also. I noticed it because a significant change in the adsense stats of one site's starting arround feb-24.
I checked the site and noticed, that when I am using adsense for maps and visiting with firefox then the next regular adsense block will not be displayed.
For me turning off adsense for maps solved the problem.
So my impression is, that there is at least one problem.
The reason I reply to your post is that yesterday started a new series of oddities and I wanted to know whether there are reports on ww or not.
I am not sure if your problem is related to mine, as I am a Premium Publisher and have a lot of special stuff and testing going on. And of course I could contact my google-rep, but I do not care that much atm to hassle arround with google ;)