I have always found PennyLane's input to be an asset to the board. When I was all-lurker, she was one of the posters who stood out to me as nice and ready with helpful info.
If her banning was a mistake, it should be fixed promptly (though I suppose the moderators can be forgiven for spending part of the day opening presents and slurping egg nog).
If her banning was intentional, then I feel someone is probably wielding power irresponsibly.
Bring her back!