Free and reduced shipping offers are ubiquitous in search results today. In fact, in some product categories, free shipping messages are now the norm rather than the exception. But can they really provide a lift to your campaign -- or are consumers increasingly immune to the message due to the very fact that it is so omnipresent?

Mark Granovetter wrote a ground-breaking study in 1973 called the "The Strength of Weak Ties." It later became one of the foundations for Gladwell's "The Tipping Point." I ran across Granovetter's work and a later follow up study by Jonathan Frenzen and Kent Nakamoto (Frenzen, Nakamoto: "Structure, Cooperation and the Flow of Market Information," The Journal of Consumer Research, December 1993) that further explored the fascinating world of word-of-mouth and how it spreads through networks. When we move this into an online paradigm, it has some thought-provoking implications.

Imagine that you are the manufacturer of the iWidget, a revolutionary product that can do everything from balance your checkbook to iron your pants. Sadly, you are forced to recall the iWidget after you discover that frequencies emitted from the device turn the docile family dog into a snarling, four-legged beast that would make Michael Vick proud. Your PR team immediately issues a press release telling consumers how to get the iWidget fixed. But because the press release wasn't optimized, when consumers search for the term "iWidget," your press release shows up on the third page -- right behind a …