I'd like to second that Facebook is a non-starter for me. You should provide an alternative that doesnt connect to facebook, twitter etc unless you want to.
I've had apps where I've been hesitant to connect with Facebook, but it's when I'm concerned the app will post to my wall or my friends' walls without my consent -- given that we don't do this, what is it about connecting to Facebook that turns you off? Is it a concern that Facebook would have access to the information in the app (they don't) or something else?
Thanks for the post -- trying to best understand so we can develop the best solution.