Samsung will most likely not have an official Ice Cream Sandwich update for the Samsung Galaxy Tab so we have to count on our favorite developers to port ICS to this tablet. Things are actually looking pretty good as some folks have managed to get CyanogenMod 9 (ICS) running on the Galaxy Tab. It’s still work in progress but many things are working, while as you can guess some are not working that well… But if you own a Galaxy Tab and want to get ICS you need to have a look.
Disclaimer: Please note that we will not be responsible if you end up bricking your device. Rooting or customizing your device can be risky, follow the instructions at your own risk.
You can see ICS (CyanogenMod / CM 9) running on a Galaxy Tab in the YouTube video below:
If you are a developer and feel like you can get the CM9 source and build it from scratch head over to XDA @ [DEV][WiP][ROM] CyanogenMod 9! - The TE4M. You will find the source link there, note that there is no ROM download link yet but it will come when it will be ready… be patient 
Here is the changelog:
What works :
RIL ( as in phone calls/messaging )
Mobile Data (2G/3G)
Audio
GPS!
Orientation sensor (although it's a bit slow, n doesnt work sometimes)
SD(s)
Wifi!
Data usage statistics
Bluetooth
Gyro, light sensors
even more...
What doesnt work :
Camera (gonna be hard!)
3D/HD Games (some games do work, like UNO, World of Goo, but heavy games like GTA wont )
probably more, although we hope to solve all as soon as we can
Don't forget to follow us on Twitter and join our Facebook Fan page to stay updated.