Well, I'm going to come clean on something. For about a year I worked at a television ratings company. I co-managed a field office for Arbitron ratings (if you do radio ads you'll know about them), where we metered and measured the viewing habits of a 400 household representative sample of the Detroit area.
TV stations take that rating data and turn to their advertisers to show them how they're good in this demo or that, so presumably the businesses will know where to put their money to effectively hit their market. So when it comes to that part of advertising, I feel pretty confident.
What I want to know is if those times the media promotes as good are really effective (I know the methodologies of collecting the samples and that their are potential flaws. The only real measure is measured advertising results, or sales leads). Did you see results proportional to the expense?