Ok, so I read this about the AdSense "referral" program...
Expanded product inventory: While many of you have had success referring one of our Google products, some of you weren't able to find a product that fit the context of your site. Referrals 2.0 offers products from thousands of AdWords advertisers, so you can find the right ads for your sites.
...on the AdSense blog and go check the "expanded products inventory" in my category.
To say it was disappointing is a major understatement.
Are there any guidelines for what categories advertisers can place their ads in? It doesn't look like it judging by the mis-categorized ads on the list in my category.