Patch 5.1 added three new items to the BMAH. The first is a weapon with a fairly unique model, the Sun-Lute of the Phoenix King!
It has a reported starting bid of 70k, the same as the Arcanite Ripper. You can find a full list of the items on the BMAH here.
The other two items are old Proto-Drakes. The first is the Reins of the Plagued Proto-Drake, which was a reward of Glory of the Raider (10 player). The other is the Reins of the Rusted Proto-Drake, a reward of Glory of the Ulduar Raider (10 player).