Well done ! This works on my JK1-flashed Galaxy Tab.
Note: I use WifiKeyboard as my input method on the tablet, to ease typing in the Terminal Emulator (or ConnectBot). It works marvelously well !
The "insmod" commands worked perfectly (thanks again for compiling...personally I was stuck at the "libc" ELF headers in my toolchain Mac OS X setup...I will soon install a Linux virtual machine so I can use the default toolchain, which contains all the required "libc" stuff...I regularly compile RockBox on my Mac so I wonder what's wrong with this particular toolchain).
I switched on Samba/SMB/CIFS sharing on my Mac OS X laptop, via the "Sharing" panel in System Preferences.
Once in "su" shell mode, I pre-created the mount point: "mkdir /mnt/cifs". I then experimented various commands, including:
- EDIT - DroidWall configured with a whitelist *prevents* the "mount" command from connecting to the Samba share, despite allowing Terminal Emulator and ConnectBot to connect via wifi...as a result I have to disable DroidWall entirely, which sub-optimal

Allowing all "root" applications to access wifi in DroidWall doesn't solve the problem: it makes a difference with commands like "ping" but the SMB mount fails to connect over the network...for some reason.
busybox mount -r -t cifs -o "username=MY_USERNAME,password=MY_PASS" //MY_IP/MY_SHARED_FOLDER /mnt/cifs
busybox mount | grep cifs
ls /mnt/cifs
umount /mnt/cifs
busybox mount -r -t cifs -o "username=guest" //MY_IP/MY_SHARED_FOLDER /mnt/cifs
Note that I chose to secure the mounted directory in read-only mode, but of course we could use "-w" instead, providing the file server accepts authenticated or anonymous connections with write credentials.
I still need to test transfer speeds...as this is often the problem with high-quality video. At any rate, I recommend using VLC Player on the server (e.g. laptop containing video/audio assets), and VLC Stream and Connect on the Android device: the live transcoding works really well !