"Let's start with a definition. Marketing is the creation of demand for a product or service. Sales is the execution of strategies that fulfill demand. For example, you send out a bulk email about your product to a targeted list. That's marketing -- you are creating demand. When fifty replies come back that need to be individually answered, that's sales. When you follow up on those fifty replies three weeks later to see if you can answer additional questions then you have a good sales program."
http://radio.weblogs.com/0103807/stories/2002/04/15/marketingSoftwareWhenYouAreASmallCompany.html