It is a push for the chest. Extra stamina is nice, but the 346 has so much mastery. Probably an wait until you get the T11 chest.
Gemming looks like it could be improved.
* Red = Parry/Mastery
* Blue = Mastery/Stamina
* Yellow = Mastery
Reforge the crab's dodge to mastery
If dodge is still closer to parry than ~2.5%, reforge the dodge in the belt to parry (minor tweak)
Chest needs +Sta enchant
Shield needs + Blocking
Wrist is a tossup - I think +sta is graded best by most, +dodge is nice too.
Bloodcraze is crap. 3% heal over 5 seconds with a 10% chance of happening. It's very, very weak. Take the 3 points out and put them in something else. I'd suggest Deep Wounds.
I've never been a fan of thunderstruck. The stacking damage buff is kinda nice, but really unneeded. 1 more point in cruelty and 1 more in sheild specialization would give you more threat than 2 points in thunderstruck.
To get Thunderstruck up to full it takes 18 seconds, minimum, if you hit TC every 6 seconds. By that time you just don't need extra threat on packs and on a boss, well, best threat on a boss has you hitting TC far less than every 6 seconds. A lot of tanks like it, but I just don't see the value. Mark kills in a pack, B+T will do the rest. Cruelty + more HS on a boss > thunderstruck.
Missing Revenge Glyph. You're using devestate, not sunder armor, so sunder armor glyph does not good. I like Intimedating shout, gives a small cc without risk of pulling other packs.