The failsafe tanking gear is somewhat confusing in 4.2.
First you get an absolutely fantastic cloak from the Thrall quest chain. Then it gets weird. The neck-piece you get after a day's worth of questing Molten Front is a threat piece, and a good one at that. The 378 cloak from Avengers of Hyjal is a direct downgrade compared with the Thrall quest one, unless you're desperate for hit-rating.
The 365 boots are a downgrade from the rep 359 ones, and the reward for pushing to honoured with the Avengers of Hyjal, a 378 belt, is suspiciously close to a side-grade from the crafted 359.
While you should eventually be able to grab some good bracers from the Molten Front quests, your 378 Valor Points option is likely a downgrade.
All in all we're getting stamina and armour force-fed to us, but the other stats are mildly put strangely distributed.
Now, the boring thing is that if the increase in stamina and armour is great enough, then it is indeed an upgrade, but as both stamina and armour are linked to the ilevel of the item, very little remains for personal configuration. At least in you stick with tanking gear. Now, if you go insane and start looking at dps and PvP gear, then you could find some gems of superior tanking gear.
Weird is weird.