Seth Godin's blog post today is about marketing (or the lack thereof) to the second circle - beyond the people who already know you, the ones who the people you know talk to about your products and services. In research we see this issue every day, clients who only want to research the people who know them well - those who have considered, purchased, repurchased, etc. This is, of course, necessary, but its only telling one part of the story. The people who are not currently considering you (or your category) may be just as viable a target. You need to understand their goals, needs, and hot buttons so you can either add them to your target set or rule them out altogether. But wihtout understanding where they stand, you'll never be able to significantly grow beyond your core market.