So in order to keep this constructive, I'm going to underline something negative and let's discuss solutions instead of just moaning about how its a problem. The negative thing is this: Syncaine pointed out, rather rightly, that MMO's have no challenge.
One potential solution is to raise the danger level or challenge of the mobs you face. This can be done through raw stats (see easy and boring way p.20) Another is through the use of scripted 'Intelligence', another is through fuzzy logic, where the game picks from several options based on your actions. And yet another is to add ... variety. Yes variety. In other words, add traps, puzzles, secret doors, surprises. Things that make this about more than just killing. DDO does this to a teeny tiny extent but I'm thinking, why do Zelda and Lufia get all the good puzzles? Why can't MMO's have some?
I'm good at making puzzles, my Fantasia game I made with Anton in college had plenty. I'm sure developers are capable. Its just that none of their management has any guts/creativity/gumption/whatever. They stick to the tried and true.. kill stuff and get phat lewts. Occasionally there are some easy puzzles, which usually involve killing more stuff in the right order or touching certain things and killing stuff.
But why not have a genuine puzzle or two? One that keeps you thinking or trying for 10 to 15 mins or half an hour to solve it? How bout lots? How bout we reward puzzles equivalently to boss battles? And why not have bosses who are not waiting around to be killed? Perhaps they have to be trapped or tricked through spying and intrigue or actually talking to citizens and planning a coup.. ok I'm just getting too creative here. But you get the idea.. what ways have video games already taught us to think inside a box that isn't really there? There are so many ways to develop an adventure that is more fun and compelling that the MOTS (More of the Same) stuff we have already.