One of the things I really like about Seth Godin is his ability to take somewhat complex ideas and industry-standard jingoism and boil it down to a pithy, yet totally insightful essence. From his Blog (emphasis mine):

“[Search Engine Optimizer]s are not a shortcut to success, at least not for 99% of the companies out there. You won’t win by fooling Google into listing you first for a common search term. You will win once you figure out the simple mechanics of turning strangers into friends and friends into customers.“

Turning strangers into friends and friends into customers. I don’t think I’ve ever heard a better description of marketing’s purpose.