..., but the data entry for powers is going to take a while, especially with having to reword descriptions so as not to infringe on copyright. ...
I don't think you have to reword any of the descriptions. According to
this article there should be no need to reword descriptions as per the Creative Commons Attribution, Non-Commercial license. Basically, just give credit to Jim B. and the The Dresden Files RPG where it is due, and don't try to make money off it, you should be good.
However, I am not sure how this applies to information taken from the pre-order PDFs. I personally am planning to hold off on releasing anything that includes blocks of text (like power/skill/etc descriptions) until after the books are officially released.
Short of Fred or another developer speaking to the contrary, I'm sure plenty of us would rather you got to spend your time making the workbook instead of rewording what the devs have already written.