I believe that even though this is an article for which you MIGHT receive compensation, you are still ok to post pictures of CryptoKitties. I think the Fair Use Doctrine has you covered, even though you agreed to the terms of service:

"For the sake of clarity, you understand and agree: (i) that your “purchase” of a CryptoKitty, whether via the App or otherwise, does not give you any rights or licenses in or to the Axiom Materials (including, without limitation, our copyright in and to the art and drawings associated with that CrytpoKitty) other than those expressly contained in these Terms; and (ii) that you do not have the right to reproduce, distribute, or otherwise commercialize any elements of the Axiom Materials (including, without limitation, our copyright in and to the art and drawings associated with that CrytpoKitty) in any way without our prior written consent in each case, which consent we may withhold in our sole and absolute discretion."

I read that section of the agreement to mean you are good to go to post pictures in a Steemit article.

Show us the kitties!