The Plumiferos team requested being able to select the parent bone of selected bones in both EditMode and PoseMode. This is useful when using a fullscreen 3d-View, so an Outliner view is not required to be able to select the parent bone(s).
Use the hotkey P in EditMode and PoseMode to access this functionality. You can also find it in the menus (Select in header and toolbox). It does however, rule out the possibility of running the game engine while in either mode, but that is a minor issue.
Interactively Setting Bone Roll
Setting the roll value of bones manually has always been a chore. Sometimes, especially on more complex rigs, it may be necessary to manually assign the roll values. However, adjusting the roll value could only be done for one bone at a time, and it was difficult to gauge what the right amount to adjust it was.
Now there is a new transform mode/tool in EditMode. You can select multiple bones and set their roll values interactively. It acts like rotating the bones around the local y-axes in PoseMode. For better feedback, it is recommended that you turn on Draw Axes for the Armature in question.
You can access this tool by pressing CtrlR
Copy Pose Attributes Menu
There were some missing entries which made rigging a bit more tedious. Now it is possible to copy Transform Locks, DOF settings for IK chain members, and even the Custom Shape setting.
It is also now possible to copy the transforms caused by constraints/IK on a bone to another bone. For this, use the 'Visual' options instead of the 'Local' options.
Custom Bone Shapes
Now there is a toggle in the armature panel to enable/disable the drawing of custom bone shapes for all bones of an armature.
Snap Bone To Location in PoseMode
Now the Snap To Location (⇧ ShiftS) tools for bones in pose-mode work correctly. Previously, only one of these tools was implemented, but it only worked in some cases (when bone had no parent and was not rotated, and the armature was not transformed in any way).
Snap Bone To Location in EditMode
Now, when both ends of a bone are selected, only the head of that bone gets snapped to the snapping point. The tail will get offset by the same amount that the head gets offset by, thus preventing zero-length bones.
After all these years, it is now possible to (re)center armatures like you can do with meshes and curves.
At the moment, you can only access this functionality from the menus (Spacebar->Transform) as the armature button panels are pretty crowded.
Constraints and other pose-level bone settings are no longer lost when joining armatures.