I agree with Nicholas that recall is a powerful indicator of ad effectiveness - there's a lot of Millward Brown data to support this. For example, advertising that's good at increasing ad awareness for a brand tends to be more effective at enhancing brand perceptions too (as well as sales). But it is only half the story. I remember a TV campaign featuring the Simpson's characters for a washing detergent in France. Great recall but the associations it created for the brand had no effect on the French housewife. So, recall is, on average, a good thing but strategy will always be just as important.
