Armatures in 2.4

Other than the rotation constraint, which rock by the way ;), is there any other core changes that would alter the way you would rig an armature to make it more streamlined and good, I guess.

Action Constraints! There is a lot more but add them all up and they still won’t beat AC’s for usefullness.

%<

could someone point me in the direction of material, other than what is right on the blender site, that will help me utilize the new features.