Personally, I am amazed at the flexibility of the UI.  The docking feature allows you to move and dock just about anything that used to float and its very accurate in terms of where you can dock.  You can close UI pieces that you don't use often (and can turn them into floating panels instead).  You can insert things that you used to have to open after poser started up - like the Python Palette.  You can also lock palettes in place so that nothing gets moved accidentally.

Wxpython is the icing on the cake.  Scripts can be built to take advantage of the dockable palettes and also inserted into your UI.  I've seen at least one script manipulate the selected figure in real time - moving multiple arm and leg segments.  There are huge plugin possibilities here.

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