Completely agree with your point that you have to go deeper to really understand audiences, and that a combination of targeting methodologies can work better than any single one alone.
To answer your question about whether you can find people who have researched diapers and donated to an environmental cause – yes, you could certainly do that, but it is not exactly attitudinal targeting. Keeping with this example, this would leave out any moms who haven't researched diapers online and who haven't made a donation anywhere recently. They are still your target audience, but their online behaviors wouldn't give you that insight. The most interesting part is that you would miss the majority of moms that fit in this group by just using the behavioral criteria. Our approach to attitudinal targeting actually uses behavioral data, combined with survey research, online/offline purchase behavior and other data sources in order to give advertisers a full understanding of the attitudes, values and beliefs that influence likelihood to purchase.
And I agree that smart targeting is critical to ROI. Of course, I believe that attitudinal targeting is the best answer to concerns about other forms of targeting, like behavioral. Thanks for your comments.