With the recent proposal for a Steganography stack exchange over on Area 51, I would be interested to know if Steganography questions are on-topic here on Cryptography.
I suggested that they might in my Area51 discussion, but it would be good to know for certain. They certainly appear to be on topic over at IT Security, given the steganography tag there, but I can find nothing in the Cryptography FAQ, and there is no steganography tag here.
So, are questions about steganography on topic here?
It depends on the question.
Modern (digital) steganography applies an analogon to Kerkhoffs' principle: Even if the scheme is known (or suspected), an attacker shouldn't be able to prove that there is a hidden message, as long as she doesn't know the key.
Such keyed steganographic schemes fit quite well into the topic of Cryptography Stack Exchange, I think.
Key-less steganography (i.e. "the scheme is the key"), as well as most of physical steganography, on the other hand, seems off-topic here.
(Just my opinion, until lots of people upvote.)
My personal feeling would be no. While steganography and cryptography are often used in conjunction (crypto to hide the information content of the message, stego to hide the presence of the information), they are quite different in many ways.
