Screenwriting : Screenwriters--Looking for some Feedback by Guy Goldstein (WriterDuet.com And ReadThrough.com)

I'm looking for expert feedback about my collaborative screenwriting program, www.WriterDuet.com WriterDuet.com is a scriptwriting program that is both free and SSL Secure. Some of the perks are: Collaborative writing--seeing all edits immediately, it's user friendly, has intuitive interface, access your script from anywhere, more focused on writing than production, grammar checker, converts to Celtx and other screenwriting formats (including Final Draft). Love to know what you think! Thanks!