The big one is that the Tracker in the AnimToolkit now works at a component level (in 2011 anyway). So if you use the Multi select tool (Control+RMB marking menu ) and select a Poly, then a transform node, the Tracker will pin the transform to the poly's normal (or vert/edge) - maintaining the offset. Obviously using the point on poly constraint under the hood. Useful... well lets imagine 2 characters interacting and you need to pin the wrist of one to the other characters chest... you can now pin at the poly level.
The Offset tool now deals hopefully with everything, audio, clips, transforms and timelines, this is at Scene level or selected level. If selected then it'll offset based on each selected node type. For animated transforms it goes through the nodes history to find any animCurves and offsets based on those. Seems to work really well and it's nice to be able to multi-offset audio, clips and nodes all at the same time and nudge their key times.
LockChannels - new UI for managing the visibility and lock status of nodes or hierarchy, very easy and fast for locking up a rig before passing to animators.
The Filtercode: major code redesign and all the calls now work on 3 levels: given nodes, hierarchy of given roots or at a scene level.