Hi,
that problem seems to be partly fixed with FCP 6.0.2, there is still a glitch in it however.
When opening the exported clips with QuickTime Player and hit CMD-J, it should show Normal Size as 960×720 and Display Size as 1280×720, as it does with anamorphic PAL (720×576 and 1024×576) but it does display both as 1280×720.
But at least the FCP-Workflow is correct, again.