What is Google Trying To Say About Me?

I use Google Reader to keep tabs on the Internet.  It's convenient & nerdy; and I'm down with that.

When I moved my blog over to Blogspot this week, all of my posts re-appeared in my Google Reader as unread.  To see if I could add a few cents to my monthly allowance, I turned on ads in my RSS feeds.  Almost nobody subscribes to my blog's RSS feed, so I figured this wouldn't offend many people.

Here's an example of what a blog post looks like with ads enabled.

Google's ads are supposed to be related to the posting that they appear on.  If that's the case, then what exactly is that third ad doing there?