stsadm can inadvertently delete a root site collection if erroneous URL path used

This is something you should definitely be aware of while using the restore command.  If you pass an improper URL path to the stsadm –o restore command with the -overwrite parameter and getting an error you notice a site one level up from the site you were trying to restore is deleted.  The root level site http://servername is deleted.

Make sure your URLs are correct (no take backs) before you try restoring in a production environment.