http://www.usatoday.com/money/books/reviews/2005-07-25-buzz-marketing_x.htm
Want to know how effective your marketing is? Mark Hughes suggests that
you ask your customers two questions.
How did you hear about us?
Would you go out of your way to recommend our product to a friend?
If they would go out of their way to talk about you, you know you've hit it.
That's customer evangelism.
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The guy who wrote the book is Mark Hughes - he's the same guy that had a town
rename itself and then eBay bought him out for $300 Million!!!