With all of this in mind, we're looking at a situation where a warrior could pretty easily reduce armor by 10 to 15% depending on spec and stance. (An arms warrior in battle stance would gain 10% actual armor reduction from his tance and around 5% actual armor reduction from his weapon, while a fury warrior dual wielding these weapons could easily reduce armor by 10-11% just from the weapons.) Mix in the effect of a trinket like Grim Toll, and you're looking at nearly 50 to 55% armor reduction during a proc. That's pretty substantial, and it's not even counting the effect of other armor pen on gear.
Two hand weapons to consider include Stormedge, Ironsoul, Voldrethar and Rune Edge. The first thing you notice when you look at them is the rather hefty amount of armor pen on these items, ranging from 70 to 84, translating to between 4.5% to 5.46% actual armor reduction. For an arms warrior in battle stance, that's between 14 and 15% baseline armor reduction: an arms warrior with mace specialization and Ironsoul, we're talking 30% armor reduction. That's ridiculously solid. Even a fury warrior can count on 10% armor reduction by dual wielding these weapons. (Sadly, Lotrafen is a polearm, so Arms won't get the mace spec benefit and fury can't DW it. I can still imagine a lot of Arms Warriors going nuts for it.) Whether or not this is a wise spending of item budget remains to be seen.
With a Grim Toll proc, you're looking at almost 50% armor reduction for a fury warrior, and an arms warrior with mace spec and ironsoul could be looking at 80%. That would mean, as an example, that a target with 10k armor would have effectively 2k armor against the warrior, while a target with 2k armor would have 400 armor, rendering him or her effectively naked. Since the more armor you ignore the better the effect (a 1% armor reduction is pretty trivial due to DR on armor, but a 10% is far more substantial) Armor Pen seems to be scaling better for warriors (who do mostly physical DPS) than for almost anyone else, especially after the Deep Wounds nerfs. (Hunters would also possibly see some benefits here.)
As for tanking weapons, there's only one thats really looking intended for tanking, Stoneguard from Ulduar-10. It's solid, better than anything outside of Last Laugh. It doesn't seem as indicative of a difference in stat weighting the way the 2h weapons seem to.
There's lots of plate gear to look at so far. Most of the drops we're getting to see are DPS plate, and most are still itemized with crit, hit, str and stam, with only the new BP having armor pen on it. ArP may be better in this upcoming patch, and may scale best for warriors out of the melee classes, but I'm still relieved to be able to gear fro crit, hit and AP as well. A look at the physical DPS neck that drops in Ulduar reveals that it will be better for anyone but a warrior due to haste being buffed for Paladins, Druids, Shamans and Death Knights, but not warriors, in patch 3.1.
There's also quite a lot of Emblem of Conquest gear to consider. It's competitive with the loot that drops in Ulduar: the DPS neck for warriors that we can buy for emlems is superior to the Ulduar drop, in my opinion. The tanking neck is very strong. The itemization here is conventional (look at the tanking and DPS plate belts) with the familiar broader application of stats so as to make good choices for DK, warrior or paladin tank/DPS. You want your emblem gear to be useful for more classes, obviously, no surprises there. There's still some interesting armor pen items as well, which is definitely indicative of Blizzard's stated goal to buff ArP if nothing else.
All in all it's interesting to look at where the itemization is going in Ulduar so far. If nothing changes (and I'd love to see more of the DPS trinkets that will drop here) we're looking at a potential renaissance for ArP at least as far as DPS warriors are concerned, while tanking gear looks to be holding to familiar patterns. One thing is for sure, warriors are going to go nuts for a weapon with 999 top end damage and stats to make you weep with joy.