Talli,
BitKeeper is NOT GPL'd. If it was, then you wouldn't be forced to do open logging. You'd be able to use the software as you please and change it. The "Open License" version of BitKeeper trades privacy for money: get the software free (as in free beer), but you have to log openly. If you get the paid version, you don't have to do open logging.
I had not heard about subversion before. It looks like WebDAV is only necessary if you're doing a network of repositories tied together, which would be good for scalability and for very lare projects. For our use, I doubt we'd need such features.
