Why does it take so long to develop nifscripts that are compatible for Skyrim? The game has been out for a year and it already exists for oblivion. To me it sounds like it can be done but the developers doesn't prioritize this. I would say it's currently the most requested feature of nifscripts.

Sounds like a question best asked on the NifTools forum.
While you are at it, you might want to ask why they are still writing their scripts for the antiquated Blender 2.49.