I have a lovely display of Daedric artefacts in the basement of my house in Solitude. Irritatingly, the Ebony Blade refuses to be held by any weapon rack (whether wall mounted or free standing). It is unequipped successfully but then falls onto the floor rather than being attached to the mount.
I had thought that this was just a sign that two handed weapons can't be mounted, however there were iron greatswords pre-supplied in them and further research has revealed that this is a known bug with the Ebony Blade. Has anyone found a method of mounting the ebony blade?