I needed to mount a Samba share from my windows gaming / media center PC to my MythTV backend so I could navigate to all my videos from a single location instead of having to worry about which server they were on. To that end I shared out the Videos folder from my account on the Windows PC. Since my user on the Windows PC is "Shahbaz Javeed" that presented a problem when trying to auto-mount it using fstab on my MythTV host - spaces aren't allowed in any field of /etc/fstab. Any spaces are considered field delimiters. The solution is to escape all spaces with \040. My /etc/fstab entry now looks like so:
//frey/Users/Shahbaz\040Javeed/Videos /var/lib/mythtv/videos/frey cifs guest,ro 0 0
This works swimmingly!