How's anyone allowed to publicly post pre-launch client work?
Does being secretive about creative work benefit or hinder?
When is the right time to show creative work for feedback?
I think Dribble has captured a solution to part of this problem, however, personally I think being secretive can do more harm than good unless it is of nature that should be kept secret.
Sharing work with fellow people in your field can help you reach a better conclusion in flushing out pages/concepts.
The best time for me to show creative work for feedback is after I've gotten at least an entire concept mocked up, but with that feeling of something isn't right, or something could be better.