I forget who said this (Paul Buchheit, maybe?), but it made a lot of sense to me: don't listen to your users, watch your users. Figure out what they're trying to accomplish -- via usability testing and analytics -- and use that to inform product development.

Feature blight is a separate issue. It's good to try out lots of stuff, but you can't just vomit out feature after feature -- you have to iterate. After you release a feature, watch how people use it. If they're not using it, tweak it or axe it. Features need to earn a permanent place in your app.