We actually have a bug filed for this issue already at http://www.jivesoftware.com/issues/browse/CS-98. Make sure to vote for it if it is important to you.
The problem with using the document title in the URL is that document titles are only unique in a particular space. That means the url would need to be the fully qualified space URL, plus the title of the document, for example:
While this can get pretty long, and may be a little frustrating to type out, the URL provides very useful information without having to click on it. As you know from Clearspace, we are pretty big fans of clean URLS, so hopefully we can get this feature in soon.