After the arrival of the 2012 jeepfan.com Rubicon we picked out many of the interesting differences.
Cargo Area
There seems to be more plastic in the rear most section of the cargo area. The subwoofer is more integrated, a 12V power outlet, and there is 6 cargo tie down areas. All good stuff. Additionally the rear glass opening is larger than 2010 and earlier.
Dash and Windshield
On the windshield there is a Jeep grille at the top above the rear view mirror that shines Jeep grilles inside when the sun hits it and on the passenger side of the windshield bottom is a Jeep climbing rocks.
The dash layout was improved in 2011. Some of the controls are changed and/or relocated. The locker switch and sway bar disconnect are now to the left of the steering wheel.