I think a lot of people are stuck in PvE gear/builds which aren't optimal for PvP. Many skills/runes that have been deemed "worthless" can really shine in PvP combat if properly applied. WD's have the advantage of constant harrassment: Haunt, Corpse Spiders, Acid Cloud, Hex, Pets, all of which are either insta-cast or follow the opponent around, preventing them from healing, kiting, or getting too comfortable.
Right now, most people gear for the minimum amount of EHP to survive, and then stack as much DPS possible to efficiently run his/her chosen MP level. PvP is going to be the inverse or that: Stack just enough DPS to kill in a few hits (which obviously doesn't need to be much if people are getting 1-2 shotted), then focus on EHP so that you are able to outlast your opponents. The P to P damage is going to need to be reduced at some point though, if the top EHP sword and board barbs are getting killed in 3-4 hits, then actual objective games, like capture the flag or even deathmatch, are never going to work.
In addition, I have seen no one mention probably the most important PvP stat: Crowd Control Reduction. I know you are going to have to give up DPS affixes to get it, bu if you are being constantly frozen, hexed, stunned, this stat can go a long way to helping if stacked high enough.
The bottom line is that top-tier PvP caliber gear is going to be very different from top-tier PvE caliber gear. Even so, this game was designed from the ground up as a single player/co-op PvE game. I imagine Blizzard will tweak some things here and there, like player to player damage reduction, but this game's PvP will never reach the level of balance found in something like LoL or DotA, as D3 simply isn't a PvP-first design. Still though, give it a few days, and there will be effective counters for every class and build.
Edited by EddardStark#1833 on 1/16/2013 10:13 AM PST