i agree... release early, release often (Score 2, Insightful)

We're in the same boat, having recently launched a web service after getting it developed just enough to elicit some user feedback.

Our new service http://www.sportsvite.com/ is intended to help people organize and play sports. We had a whole slew of a priori ideas regarding the features people would want for this type of service... BUT, after getting great feedback from our initial users, we were able to prioritize our requirements and fine-tune our plans for following releases.

Bottom line -- for these types of web services, it makes all the sense in the world to get it out there fast and essentially evolve the service alongside the users.