In his book The Lean Startup, Eric Ries argues that for any viral strategy to work, the viral coefficient has to be greater than one. Or to put it simply, for each person that uses your products, you want to automatically trigger at least one additional person to become a user. The higher the viral coefficient is, the more successful your viral marketing strategy becomes. Once you have a successful viral strategy in place, the challenge becomes not to limit its explosive potential growth.
I recently received an email from a search engine marketing (SEM) professional that may be of interest to our readers. So I am sharing with all: