Ok, so here I am in proudspire manor trying to mount ebony shields on the shield racks when I notice the second I equip them that they're invisible.

No biggie, I try to mount them on the shield rack and the game says I need a shield equipped to do so.

I did a google and board search and came upon this:

http://forums.nexusmods.com/index.php?/topic/474758-invisible-ebony-shield-vampirism-bug-report/

Same bug I'm experiencing. I cured my vampirism to test it out and it worked. The second I became cured, the shield equipped as normal.