I pretty much agree with Kamikaze Midget.
One of my major gripes with 4th edition is that the character classes are now purely wads of combat abilities, and you're supposed to just extemporize everything else.
For example, a rogue is no longer someone good at sneaking, stealing, disarming traps, disguising themselves, finding information, climbing, hiding, etc. A rogue is now "do damage, do damage, do damage" -- nothing but another variety of fighter.
In fact, everything is now a variety of fighter, variants of two basic fighters -- ranged fighter and melee fighter.
Everything is defined by combat. You often can't heal someone without smashing something on the head. There are very few class powers that you would ever use out of combat. Just looking at a 3.5 class, you perceive it as a representation of a creature which could exist outside a battle. Looking at a 4.0 class, you see nothing but a wargame piece's statistics.
Yes, I know you're supposed to add everything else in yourself. However, I can do exactly that with a game of Sorry or Monopoly. I can make up whatever individual personality and background I want for the individual pieces, there, too. But that doesn't make Sorry or Monopoly a set of role-playing rules, and to a great extent ,that's also true of 4.0's rules.
They've been abstracted to the point where they mean nothing except as a game, like the pips on dice in craps or the spades on a card in bridge. They are so divorced from representing anything that it's impossible to consider 4th edition to be a role-playing game any more -- it's an abstract wargame.
Yes, you can role-play with it, but only in the same sense as you can role-play with chess saying "hah! My pawn just took your pawn -- and that really represents him sneaking up through the bushes and shooting him with a crossbow!" That is role-playing, but it does not make chess itself a role-playing game. Precisely the same is true of 4th edition D&D.