For advertisers, behavioral targeting is definitely useful. But that importance is not clear to some consumers. In fact, studies show that there is a huge difference between how users feel towards privacy and what they actually do in light of this concept. When it comes to behavioral targeting, it has been shown that consumers have different levels of skill and knowledge when it comes to privacy. This is the summary of an article by Donghee Yvette Wohn and Chandan Sarkar. You can get the pdf of the behavioral targeting article here: Expertise Matters: Privacy Perceptions and Practices in Response to Behavioral Targeting.