I've made posts about gems and glyphs, now it's time to move on to enchants.
Just like gems and glyphs, enchants are great things to get. My main is an enchanter, and while my other profession moves around a bit, I can't ever imagine dropping enchanting. But enchanting really isn't what it could be, and much like gems and glyphs, this has a lot to do with the selection of enchants that are available.
Looking at enchants for various slots, there are generally three or four different "top level" enchants for each slot, that is, enchants that give the maximum possible number of stat points. In gloves the expansion brought both Expertise (15 expertise rating) and Precision (20 hit rating). While given that choice (and only that choice) some characters should take Expertise, the Hit rating is the more powerful enchant.
In gloves you get to choose between AP, Spell power, Agility, Hit and Armsman.
In cloaks you get to choose between Agility, Haste and Armor
In chests you get all stats or Health
In boots you get Tuskar's Vitality unless your class gets to run fast, in which case you can choose between Agility and AP
In bracers you get to choose between Stamina, AP and Spell Power
The question is, are there any interesting choices to make here? In reality, the closest any class comes to an interesting choice is knowing whether AP or Agility is better for your the spec you are in. Probably the only place where enchants are really interesting is where one stat is so brutally unbalanced or desperately needed that it actually makes sense to take a hit to your stat points in order to convert them to that stat. For example, if one strength is worth three or more AP, as it was for Unholy DKs for at least part of the expansion, then you should get the Major Strength enchant from BC on your gloves instead of getting Crusher.
In reality aside from the agility/AP classes, the choice of enchant is a transparent non-choice for even a novice player with no theorycrafting experience at all. If an arcane mage has to choose between Haste and Crit then there is a right answer and a wrong answer for maximizing damage, and so you can say that the choice can't really be all that interesting. But a novice player has the option of customizing; diminishing returns on one or the other stat might affect their relative weight as your gear changes (for example, Crit might proc an ability like Flurry and be less useful per point when you have 40% than when you have 20% because of the chance in how it affects your Flurry uptime); and at least in order to figure out which stat you want you need to know something about your class mechanics. Choosing between Spell Power, AP and Stamina on your bracers isn't a real choice for anyone.
Enchants that do more than simply add a stat make enchanting more interesting in a way, but often make choices less interesting. Armsman is the tanking glove enchant. It's hard to imagine a tank using another enchant (aside from tinkering armor on with engineering), and no non-tank would use it under an circumstances. Tuskar's Vitality fills the moving faster gap for specs that can't talent it, and I'm not even interested in arguments that a small number of stat points can be better than 8% faster movement. Those arguments have played themselves out already. Except in cloaks (where people don't use the "special" enchants) there is only one special option per slot, and that special option is either useless or overpowered depending on your spec.
I don't think that increasing the selection of enchants is really going to do the trick. Each class has nearly 30 major glyphs to choose from and there are about 50 epic gem cuts, but all that variety doesn't increase the breadth of rational choices very much at all.
Changing enchants so that we choose between stats that we might actually want to choose between would help, though. If I could choose hit, haste or crit to wrists then my choice would depend on my spec, my current gear, and to some extent the fights that I was facing, instead of depending only on my spec.
Adding more enchants with "special" effects that are useful in a wider variety of circumstances might also improve things. Engineering shows that they have the capacity to do enchants that give items use abilities. More enchants like this, where you get to choose between an on-demand boost and a constant passive boost, would give more leeway to choose enchants based on a style of play and on fight mechanics rather than simply choosing the one that is best for you on a spreadsheet.
Of course there are some major obstacles to overcome. If spell power is as out-of-whack with crit as I suggested it would be in my recent post of rating conversions then in order to make a glove enchant tempting for a mage, they might have to make it give 140 or more crit rating, since otherwise the WotLK spell power enchant would beat it out. I don't expect crit rating to be that far back from spell power in reality, but I wouldn't be surprised if it were no better than a third of Intellect for most caster classes when Cataclysm arrives. Old enchants would be taken over new ones because stats are so desperately out of scale with one another.
My prediction on this is that enchants will basically be the same as they are now when cataclysm comes out. All the casters will enchant Intellect and lament it when they can't. All the tanks will enchant Stamina and have similar complaints about that option not being available on every slot. I don't think enchanting is quite as degenerate as glyphing, and neither are even close to gemming, so I expect it to get the least attention. And all of these things have to compete with their ultimate goal for customization: making talents into real choices. If they can get that right then they can probably rest on those laurels of character customization for the entirety of cataclysm and not worry so much about the homogeneity of enchants, gems and glyphs until next expansion.