iOS 5.1 is released, and Apple is still signing iOS 5.0.1 for now, but doesn't look like it could go anymore wrong for you at the moment.
I have never seen when a DFU restore fails to resolve an issue. The only time I have seen the progress bar stuck like that is when the /etc/hosts file has been modified to include gs.apple.com - but you've tried different machines right? All with the latest iTunes, and an unmodified hosts file?