I don't know about you, but I often find my content on other Web sites that have not asked me permission to use my content and without a link back to my Web site. Plus, what makes it worse, is that they have Google's AdSense ads on the Web site. So they are making money on my content and no credit or revenue is being shared with the content's creator. I am sure I am not the only on in this boat, if I was, Google would not have added this information to the AdSense FAQ.
A moderator from WebmasterWorld named Jenstar summarized the new rules here. Or you can visit the AdSense FAQs page on the copyright topic.
I say its about time!