The new option tree structure is neat (talking V 2.12.03 here).
Just one thing I stumbled over: The icon buttons for choosing a file/folder (e.g., defining a new Search Folder) are not part of the 'Tab Order', i.e., hitting the tab key repeatedly will never reach those buttons.
For a keyboard-centric tool, I would it welcome if they could be :-) (In fact, every field, check box, etc should be in the tab order, I just didn't check every option dialog. Also, on some dialogs the tab order is not from left to right, top to bottom, but is jumping around a bit.)
Cheers and Keep Up the Good Work(tm),