Google Adsense policy has changed. The announce about it here. you can also see it when you login to your account. So what has changed it in?
The most common change in the policy is that most instances of “Website(s)” is changed to “Property(ies)” to take care of the new Adsense avenues like gadgets. The second major change is the privacy policy where you need to have a privacy policy on your site which need to mention about cookies.
Here are the other changes (other than the mentioned above):