ROS 1.2.0 has been released along with ROS C Turtle RC 2.  Now that
ROS and remaining stacks have reached 1.2 status, the final C Turtle
release will be happening soon. We encourage integrators to continue
to reporting issues.

You can read the change list for ROS 1.2.0, including migration notes, here:

http://www.ros.org/wiki/ROS/ChangeList/1.2

For more details on RC 2, you can read here:

http://www.ros.org/news/2010/07/ros-c-turtle-release-candidate-2.html

RC 2 is a minor update to RC 1. ROS, geometry, and
pr2_ethercat_drivers have officially been marked as stable. There is a
bug fix for PR2 users for gripper calibration as well.

 -- your friendly neighborhood C Turtle team