1) The document analyzes the importance of the "long tail" in search engine marketing campaigns. It presents research on whether success is driven by a large number of less popular keywords or a few important keywords.
2) The study tested three hypotheses: that the distribution of searches, clicks, and conversions is concentrated among a few keywords; that increasing the number of keywords has little effect; and that the most popular keywords capture most future activity.
3) The results supported all three hypotheses, finding the distribution is concentrated, increasing keywords provides diminishing returns, and the most popular keywords predict future success, not the long tail of less popular keywords.