Interesting question. I'm not sure how it would work in a cedar humidor, though perhaps some good traditional tobaccos would be interesting. That said I'd hate to taste some of the drippy American tobaccos with a cedar note.
Then there's the giant plastic/glass humidors that aren't cedar that just control the humidity and temp. I'm guessing it wouldn't make enough of a difference to bother with but that said I have no idea.