Went thru the whole ISO 9000 stuff back in the day and it does work as long as everyone in the team adheres to the process. One broken link in the chain and the whole thing literally unravels.
Call me crazy, but the way I apply the 80/20 rule to my online business is to provide no customer service. No contact phone or email on the site.
Customer feedback is actually part of the process. To eliminate noise calls, I only supply a non-800 # for serious inquiries. Toll free phone #s encourage any old crank to call for any old reason, not interested. I also have no problem telling someone I can't accommodate their needs if it;s too far off target and I'll refund so fast it'll make your head spin to get rid of a problem customer.
However, if you never listen to what your customers are saying, you risk missing out on new trends and suddenly your product could become irrelevant.