New Patch notes for 2.2 have shown us the requirements for the tank mounts, and there's new titles for tanks to go with them.
They seem like they would take a long time to get so it probably wont result in a huge influx of bad tanks to get the mounts as we had thought.
"A Tankless Job I (Paladin) Complete 50 high-level full party duties as a paladin. Title: the Meat Shield
A Tankless Job II (Paladin) Complete 100 high-level full party duties as a paladin. Title: of the Stalwart Shield
But Somebody's Gotta Do It (Paladin) Complete 200 high-level full party duties as a paladin. Item: Warlion Horn
A Tankless Job I (Warrior) Complete 50 high-level full party duties as a warrior. Title: the Meat Axe
A Tankless Job II (Warrior) Complete 100 high-level full party duties as a warrior. Title: of the Stalwart Axe
But Somebody's Gotta Do It (Warrior) Complete 200 high-level full party duties as a warrior. Item: Warbear Horn"
As of patch 2.2, the following trials and raids will count toward achievements requiring the completion of high-level duties with a full party:
The Howling Eye (Extreme) / The Navel (Extreme) / The Bowl of Embers (Extreme) / The Whorl Eater (Extreme) / Thornmarch (Extreme) / The Binding Coil of Bahamut (excluding Turn 3) / The Second Coil of Bahamut