handhold

I run a startup web app and I am looking for more feedback on what current users like, dislike, if they share it with friends, what they'd like to see implemented etc. Is a survey a good way to accomplish this or should I take another approach? I already have a feedback button on the site but I think the feedback it captures is only a small segment of my user's thoughts. If I do a survey, which users (heavy, light, new, old, all) should I send it out to and what other questions should I ask? Does anyone have a survey already prepared they'd be willing to share? - Thanks

I run a social music website that is getting a steady stream of visitors (1,000) each day. We've been on the front page of Reddit (several times), featured in newspapers, blogs, podcasts etc. while these help us grow, our growth rate of active users isn't tremendously high. We have recently created a Facebook app to help spread the word about our site. Is there anything else that can be done to increase growth other than wait for positive word of mouth?