I just saw that if I need to install the latest Cyanogenmod on my tab (Galaxy Tab 2 7 (GT-P3113)) I don't need to root it. Is this true? Any one have more information on this? So will it be easy to restore to the original rom?
Technically, you don't need root if you have an unlocked bootloader. Even if it is locked, you don't need root, you just need an exploit to change the recovery to install CM9/CM10. Usually, the first thing that people do when an exploit is identified is "root" the device but flashing a different recovery and flashing a different ROM is also possible. Root happens first because there are little or no modifications that have to be made except put the
su binaries on the device.
The Galaxy devices, from my experience is actually pretty easy to "Restore to Stock" if you so choose. It does require a little research to find the stock rom files and the use of ODIN (or hemidall). Once you have the stock files that can be used with ODIN, it is rather simple to restore to "stock"
With CM9 and later, you do not have to have root enabled. On top of that, you can change that when ever you want. You can also specify if you only want to allow apps to have root access, only adb, or both.