forum n00b here. I have a TJ and have been itching to upgrade to the JKU. Like all of you, i am waiting on a diesel as well. Because i live in San Francisco, CA, i dropped by the local dealership to have my first look at the inside of the JKU. Loved it. Chatting with salesguy, i brought up the diesel question and his take was simple. "not going to happen anytime soon". Pressing him about the GC having a diesel and releasing shortly, he was pretty sure that even if it release for the US, it will not meet CA emissions.
I left the dealership quite disappointed. After hearing about the new pentastar transmissions being ready to receive the VM motori diesel engine, i had my hopes high that it would happen as soon as 2013. Now, that seems unlikely.