"Interesting" stats
I think you're approaching it as a player, in which your goal is to improve your character as much as you can as fast as you can. From that viewpoint, any piece of loot that isn't an unambiguous upgrade just gets in your way. But think for a moment about the over-arcing design of loot in the game and the role it fills. Deciding what is an upgrade is part of the challenge in the same way figuring out to beat the boss is part of the challenge. The hit stat represents a gearing challenge because you can't just assume any loot from Icecrown is an automatic upgrade. It may be a huge upgrade. It may be a sidegrade. It may be a slight upgrade, but only if you swap around a couple of other pieces, consider regemming, etc.
In short, you have to game it.
Put another way, even if there is a "best in slot" list for every spec, the order in which you get those pieces is significant, and makes you have to think and solve problems. That's why I call hit "interesting." Spellpower, while quite desirable, is not interesting in that more is always better to the extent that we can't even offer variation on it from one piece to the next any longer. The rating-based stats, especially those with caps as low as hit, cause you have to solve the puzzle in order to wear them. There aren't a lot of huge decisions you make in WoW, beyond perhaps your class and maybe your guild. But there are a lot of little decisions that when taken together make the game fairly compelling.
Too often players approach gear design as "I would never wear that piece, therefore it's a badly designed piece." But consider for a moment that badge vendor +hit trinket again. It might not be attractive to you personally assuming you're hit capped in your current gear. Your conclusion might be that the trinket was itemized wrong. But that might not be the conclusion of say a Resto druid who decides to try Balance and now has a huge hit deficit to overcome. Regemming or farming old content is one way to do it, but relatively slow and / or painful. Getting a shiny new trinket off a vendor (i.e. isn't even subject to the whims of boss loot RNG) with a whole bucket of +hit on it starts to look pretty attractive. Just because the piece isn't for you doesn't mean it isn't filling a gap in the fabric of the game. (
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+Hit bonus
I will agree that the complication from hit that comes from bosses being higher level than characters, along with the difference among melee and spell hit and dual wield hit make the system more confusing than it needs to be, and the various raid buffs (and particularly Heroic Presence) can put you in a mode of constantly swapping around rings and bracers or whatever. This is something we'd like to improve. (
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Spellpower, AP, and Armor Pen changes in Cataclysm
We're changing spellpower, attack power and armor pen for other reasons, not really because they're confusing. For example, armor pen is almost impossible to balance because of the way armor works. Spellpower we're actually pulling because it's too boring -- it can virtually be derived from item level and we figure if we have to put both it and Intellect in equal proportions on every piece then something's wrong. AP makes us split leather stats in weird ways that make it attractive to warriors and hunters. It's just a cleaner design where everyone has a primary stat: Str, Agi or Int. Those are simple explanations to the point of almost being inaccurate, but you get the idea. (
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Not enough Emblems of Frost?
I am fairly confident we will all be drowning in Frost in several months wishing we had something else to spend it on. They feel precious now because the income is low because there are so few Icecrown bosses available (coupled with the fact that you aren't getting much non-badge loot because so few Icecrown bosses are available). (
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Death Knight (
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Death Knights Offtanks
I don't think "offtank" is a role these days the way "healer" is a role. Most guilds have a main tank that they use on single target encounters, then they have a second tank that they use if the fight needs another tank. Maybe the MT is a better player or shows up more reliably or maybe she's the guild leader or maybe that's just the way the guild has always done it. For these guilds, presumably the warrior tanks Onyxia and the DK picks up the adds. On Twin Valks, each of them tanks one boss. On Mimiron, the DK probably doesn't do much tanking until the end. I wasn't trying to imply that DKs have a set of abilities or stats that make them suitable for OTing but not MTing. I was just pointing out that there are a lot of guilds with warrior MT and DK OT. I can't say for certain that this is the most common setup among cutting-edge guilds because I haven't looked lately, but my hunch is that is the case. There are actually quite a few different combinations of MT and OT that get used, which is a good thing. (
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