Last night I successfully tanked Maiden, which was my first.
I am not sure if it was inexperience but she is one of the most difficult fights in Karazhan for a tankadin. I was constantly silenced which prevented me from generating threat at a fast rate. Luckily I had two hunters in the group, which miss-directed and helped build my threat. But without them, I can see this being a long fight.
At the end I received my first epic tanking gear from Karazhan, Iron Gauntlets of the Maiden.
I am now at 101.55% total avoidance.