JK is the newest Wrangler style. 2 and 4 door, 07 up I believe.
Here is a good site that's strictly XJ. http://www.naxja.org/forum/
It's a fun thing, just watch out. It will turn into a epic money pit because you want to change or upgrade things not to mention breaking parts if you aren't kind to the gas pedal. It can be a challenge doing what some people say can't be done. There was a guy that had a big block in his XJ. Insane.