First Ad Age Search Marketing “Fact Pack”; Includes List of Top 20 Agencies based on SEM/SEO Ops
http://www.adage.com/images/random/searchfactpack2006.pdf
27 pages; PDF.

Ad Age is a leading trade pub in the U.S.

   In addition to the “facts” you’ll find the, “first ranking ever of search advertising agencies based on estimated revenue generated by SEM/SEO operations, presents the top 20 agencies.” Glossary too!

From the intro:

   For example, …on Page 30 with a case study of the term “HDTV.” Or check out the cool eye-tracking study detailed on Page 40 to see what search marketers mean when they talk about the “Golden Triangle.”

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