It seems these days that crafting as a main element of a game is falling to the wayside. Crafting is entering a niche market, and appearing only as a paltry, token system in most MMORPG's. The WoW model seems to be the most common one, where crafting provides occasional gear, but usually anything that can be made is less useful than things that can be looted fairly easily.
The real question is why. Obviously there is a some market for crafting, as many vocal MMOers clamor for crafting systems in every forum on the internet. These crafters want an in-depth and expansive system that will keep them entertained and model complex economic systems within the game. So why isn't this market being met?
The easy answer is that it takes a lot of resources to invent a powerful crafting system. Star Wars Galaxies had a massive crafting system where each item was tagged with a unique number and was unique. Obviously developing and maintaining the database for such a system would be difficult, but more difficult would be balancing these items. At one point, composite armor was sold that had a ridiculous defense rating, making pvp against people in that armor a real joke. The defenses were so good that players began using weapons that were basically trophy trinkets that did very little damage and no player had certification for (using a weapon without certification severely reduced it's damage potential) because they did a type of damage that wasn't mitigated by the high defense composite armor. These weapons (which literally did about 20 damage all told) did more damage than any other gun could (regardless of user skill or perfectness of the crafting of the gun).
Balancing, creating, and maintaining a crafting system becomes more difficult with the increasing complexity of the system. Resources are limited in MMORPG production, so this is pretty much the dump stat of any MMORPG. 90% of the fanbase won't care if the crafting system is mediocre, and that remaining 10% is still homeless and looking for a place to call their own. they will most likely buy the game, and quit later, so why bother creating a system to attract them?