Not sure where the best place to post this. But came across a problem tonight which looks like a potential bug. In blog settings. You are able to clear blog title and tagline and save with no ill affect I could see. As soon as you then attempt to clear WordPress address and save, this completely breaks the blog and sends it back to the install page everytime you hit either the blog web address or the wp-admin.
To fix this I had to manually add these settings back into the database but from a user perspective you shouldnt be able to clear these values without sufficient warning.