I’m running fuppes on my DroboFS, I have have the “media” directory as a symlink to where my media is stored on the Public share, and I’m able to watch MP4 movies on the PS3 just fine. I’m also running firefly and have it pointing to the same media directory. Multiple streaming media services, one copy of the media and all contained within the same location for easy management.
ls -l /mnt/DroboFS/Shares/DroboApps/fuppes/media
lrwxrwxrwx 1 root root 33 Dec 5 21:56 /mnt/DroboFS/Shares/DroboApps/fuppes/media -> /mnt/DroboFS/Shares/Public/iTunes