Is it the loyalists, the screamers, the complainers, the vocal fans, the silent fans, the professional critics, the amateur critics, the competitor's customers, the uninitiated, the lapsed users, the heavy users, the idiots, the geniuses, the accountants, the President, the bloggers, Oprah, Martha? All of the above? Prioritize the different groups? None of the above?
Who will give you the best advise?
The best answer may be a combination of inputs from Bob Hoffman of Hoffman & Lewis and Seth Godin.
Seth says "listen to your "Sneezers" - the people who tell the most people about you (good or bad). Listen to the people who thrive on sharing your good work with others. If you delight these people, you grow. "
But what if you are just starting out and/or you don't have sneezers?
Find the people who sneeze about products similar to yours and see what they think of you.
Bob Hoffman thinks that appealing to the heavy/high yield user is the key. Given their knowledge and use products in that category, they pay the most attention and are the de facto experts in the category. Also, it is the brands that attract the most heavy/high yield users that dominate a category.
O.D.O.o.O.D.B.