Cast Your Vote: Attic Flooring Survey

I'm in a quandry about what kind of flooring to put down in my newly renovated attic and wanted to hear your opinions.

This room is on the north side of my house and is above my living room. I'm going to use the room as my craft and exercise santuary. The entire house has hardwood flooring. The floor of the attic isn't totally level so that's one concern about putting down hardwood.

Should I put down hardwood floors or carpet?
If I go with carpet, I'd put down a nice thick berber.