Thats a really great article. Thanks for sharing.
The company i work for tries our best to keep our existing customers. The tech support division does their best to get back to the inquiries within 24 hours. We also have a forum, and their problems might have been answered there before.
Some of the customers have been so kind to give a testimonial about their wonderful experience with their product and to some future clients, reviews such as those are of importance. It attracts new customers as well.
So it pays to take care of your existing clients.