I just signed up for Google AdSense. I figure, no harm in it. Never know, I might even make a little loose change on the side. Now, I don't know if it is linked or not, but about half an hour after I signed up, the Google Bot did a very thorough spidering of the site. If it is related, I am sure they are looking for red flags like pornography and illegal downloads. If it's not related... it's about time they did such a spidering ;)
Of course, I also need to get approval by Google, but hopefully that should happen soon.