Don't think we've seen a Blue confirmation about Resilience yet.
If it really is a direct counter to scoring a critical hit (which would explain the absense of Resilience on the Paladin retribution Arena set) instead of a way to dumb down the additional damage caused by a critical then a lot of classes will be afflicted by this on their performance.
It also adds a very curious implication to PvE as well.
http://forums.curse-gaming.com/showthread.php?t=12507
The sets have been altered slightly for some classes.
Details are now known on regular honor items as well as L70 blue weapons with "High Warlord" in the name
Meta gems are peculiar gems that add unique effects like 5% root/stun immunity or 2% chance on spellcast to make the next spell you cast instant or provide +20 attack power and a random chance to stun your opponent for 2s with melee attacks.
The stun metagem requires 5 red, 5 blue and 5 yellow gems to be present in your entire outfit.
With only 6 gem slots in the Arena Armor this was impossible to provide - however three additional armor slots are now available for regular honor points from the generic PvP vendor apparently - boots, belt and bracers (all epic at L70).
There's an epic L70 neckpiece available as well in caster and melee form.
The bracers and the neckpiece both have one gem socket each bringing the total sockets you can accumulate from PvP-ing only to 8.
That just happens to be enough
sockets to piece in the 5/5/5 red/blue/yellow gem combo to activate the metagem in your PvP suit.
Also available from just PvPing, epic vendor honor-point acquired red and yellow gems (and their combinatory color - orange).
These two primary colors add offensive stats.
Only problem so far is that Blue gems (and in particular the gem color combos Purple and Green) are not spotted/leaked yet; those are required to activate at least the Stun Metagem (Earthstorm Diamond, I believe).
Then again, all PvP honor/arena acquired items feature only red or yellow sockets.