The one area that I have to give an A for effort but F for functionality is the "Improved joint orientation behavior when moving joints." This area of Maya, while extremely flexible, causes many, many problems for character riggers both new and experienced. The joint orient tools as they exist in Maya don't work for joints that are off axis. They must be on a flat plane. To make things worse, instead of fixing or adding what was needed to fix this to the joints, they put another option on the move tool that is flaky at best.  It is true this fix could be helpful when your first drawing out a skeleton, but that is it.  The orient joint tool has some limitations when a joint is rotated. It errors out, and even if the joints say 0.00, sometimes it will still err telling you it can't work because joints are rotated.  The other issue is that because this function is part of the move tool, if you interact with the joints in any other way with another tool or script, we lose this new functionality.

The last and final reason I won't be using this feature this year is that it has its own settings for joint orients follow, so if you don't make sure that it is set to match what the joint tool was and/ or what the current fixed orient is, then it will reorient the joint with some preset orientation. What it needs to do is query the selected joint and figure out the current orientation is and update it, not reorient it entirely based on some other set of settings.

On a positive note all deformers can now write out their weights to an XML format file as a much needed replacement for the image based method of the past.

MotionBuilder 2012
Having been part of the pre-alpha group for MotionBuilder, this update is kind of an adjustment for me with the new Dark GUI, updated character picker, characterization tools and fcurve editor changes. Back in version 1.0 of MotionBuilder, the first request we had was for them to give us a dockable GUI, and now we have it. Gone are the extra space-wasting window borders, and in its place are thin small drag able splitter bars allowing the user to adjust the layout quickly. The one gotcha is that the main timeline will no longer let us be adjusted taller to make seeing and editing keys in the timeline easier.

As previously noted, HumanIK got a big overhaul with a new unified interface and solver between Maya and MotionBuilder. I think for new users who are getting on the software it will help the transition from Maya to MotionBuilder as animation needs grow or the volume of work can be done faster.

For experienced MotionBuilder artists, the new Dark GUI and larger, more subtle character picker is a bit frustrating and does not provide clear enough feedback at a glance like the previous one did. There are good parts. The FK rig is pick-able directly from the GUI and the auxiliary pivots and controls are more nicely organized than the hidden popup that existed before.

Speed and MotionBuilder are synonymous animate and playback at your final frame rate without having to stop and playblast. To help keep you running as fast as possible there is a new tool call the Profiling Center. "The new Profiling Center window includes tools that allow you to monitor scene performance and determine where performance cost is highest." I used it to go from 28fps to 40fps with a few tweaks to the configuration on a heavy file.

With every major release the .FBX format gets an update and this time support for Nurbs Curves was added. Creating custom rig controls out of curves is common practice, and now those can be sent over to MotionBuilder to use for rigs created there over the HIK rig.