Top PvE Gear used in PvP
One of the problems we had last season (and the first season when you think about it) was that you need a minimum threshold of resilience to really be viable. A change like this would only make that curve steeper. Having 1000 resilience would be even more powerful than having 500 resilience.

We do want PvE gear to be a decent substitute until you can collect enough PvP gear. The PvE gear was too dominant in some cases in the previous season, we think because:

-- When everyone's resilience is low, doing damage quickly becomes even more important, so gear that doesn't "waste" stats on resilience become more optimal.

-- PvE gear from Naxx, particularly the KT weapons, were easier to collect than the PvP equivalents. That isn't going to be as true in this season because Ulduar is more challenging and the higher item level weapons from PvE are going to be even less accessible. (Source)

Amount of class changes in future patches
That said, I don't think you will continue to see as much class change for the rest of Lich King. Many of the changes in 3.1 were to address problems introduced when we made big changes in 3.0. You can look at the classes that have had the most iteration, and in most cases those are the classes who were restructured a little bit in Lich King: warlocks, hunters, priests, paladins and the new class.

We will continue to tweak numbers up and down as needed, but I would not anticipate as many talent or mechanic changes for the next several patches (though there will be some). (Source)

Class balance and overpowered specs
I don't think it's that formulaic. I'm not going to list the classes or specs that have historically been powerful in the various Arena seasons, because that will just turn this thread into various players jumping in to argue about how they really weren't that powerful. But many of them did not have every item on your list. Sometimes a single powerful ability can make up for a lot of "lacks" and the truth is we like for classes to ultimately have strengths and weaknesses, not just a whole bunch of strengths.

If you look at the classes that are powerful now and those that have historically been dominant, I think it comes down to two things:

-- A mix of offensive and defensive capabilities, especially active (i.e. non-passive) ones.
-- Being a good complement to the abilities, strengths and weaknesses of other classes in order to make a strong comp. (Source)

Warlock (3.1 Skills List / 3.1 Talent + Glyph Calc.)
Upcoming Warlock PTR changes
Fire and Brimstone -- After a lot of feedback and testing, we think we are going to change this again. Now increases the damage done by your Incinerate and Chaos Bolt by 15% on targets afflicted by Immolate, and increases the critical strike chance of your Conflagrate by 25%. The first portion of the talent is now a pure percent boost instead of modifying the “bonus” that Incinerate gets. It was too confusing to players and had some weird side-effects, such as Chaos Bolt not scaling well with Incinerate if Incinerate did more damage.

Incinerate and Immolate -- There does seem to be a bug where spellpower is not getting applied correctly. We don't know at this point if this is an old or new bug. Certainly there used to be a lot of spells that didn't scale with spellpower, though we now make an attempt to make sure almost all of them do. It may matter less with the F&B change, but we'll still get it resolved.

Conflagrate -- We still intend to leave this as it currently works on live (not consuming the Immolate).

We understand sometimes players can get whiplash from our rapid iteration. That's just the way we designed, though we perhaps have not always communicated the design churn as openly as we do today. (Source)