Blizzard is preparing a hotfix to buff resilience that should be in effect for the remainder of the Wrath of the Lich King expansion. Here's what the buff will mean for players:
"The change will double the value of resilience in reducing damage done by players. So depending on their current amount of resilience, characters might experience a 10 to 20% decrease in damage taken from other players. The critical strike chance and critical strike damage reduction components of resilience will remain unaffected by this change."
According to Bornakk, Blizzard has also "prepared some further changes that will allow us to quickly deploy a PvP-only healing adjustment if we feel it is warranted." The resilience change should be implemented while we're between Arena seasons.