It used to be that developing customer relationships in a mass- market economy didn't matter. All a successful company had to do was make products that people generally liked--build it and they would come. Patricia Seybold thinks those days are long gone. Thanks to the Internet, customers matter more than ever, and companies that don't get it simply won't make it. In The Customer Revolution she writes, "For the first time in the history of modern business, it's now cost-effective for companies to establish relationships with each and every customer who wants us to know him."