Just FYI, there is NO Adventure Journal 2.0. If you see a 2.0 version anywhere, it is fake.
The next version of AJ will be called Adventure Journal 2, and it will be a completely separate theme due to DRAMATIC differences in the way it's built and structured (unlike AJ 1.x, AJ2 will not be based on TwentyTen or TwentyEleven).
Generally, the look of the theme will be staying the same, and the same list of headers will be included... but behind the scenes, the entire theme has been rebuilt from the ground up. There will probably be one more update bringing Adventure Journal to 1.8, but going forward AJ2 will be the only one that is actively maintained.
Adventure Journal 2 should be available by the end of May.