If the product is aimed at a mass market, how can you be sure yout customer stories are representative of the whole market?
  --CayteLindner

This problem is no better or worse with EvolutionaryDelivery than any other kind of software (or any other consumer product). The usual techniques apply:
	* Good marketing folks
	* A strong and clearly communicated vision of the product
	* A clear connection to real customers (asking your spouse, focus groups, etc)