I for one welcome our new focused core class overlords!
It looks as though in 4E, all the classes are going to have a tighter focus to them. In previous editions of the game, the six or seven TRULY core classes were such generalists, that you could run pretty much any archetype with them.
This led to a lot of supplements with increasingly contrived core and prestige classes that really didn't do much that a core class couldn't have done. This probably also contributed to power creep as designers were forced to push the limits of what a character class could do in order to differentiate them.
Under 4th edition it looks like the classes are going to be much narrower in scope than before. Instead of a core rogue that can perform just about any rogueish role, its going to have a narrower focus, perhaps on thievery and stabbity-stab-stab combat ability.
If you want an social "con man" rogue, perhaps that's going to be covered by the Bard class when it comes out. Or some other class altogether.
Just like the fighter seems to be focused on heavy armor approaches, if you want an agile fighter, that might now be the province of the ranger class.
The classes are becoming more distinct, and I think that's a good thing.
I think the argument that "I want to play X now!" and "Everything should be in the PHB from the get-go" is fallacious. In the first place, that leaves no room to expand the game in later supplements. In the second place, its just not possible so its really a question of whose preferences get included. Personally I could care less about Druids, Gnomes, and Bards. Others may feel differently, but I suspect more people share my view than don't, otherwise they would have gone another route if those were among the most popular elements of the game. You certainly don't see them dropping fighters, even though the fighter archetype can be handled by the Paladin or Ranger. Fighters are just too popular. Many of the elements that have not been included just don't have the same amount of adherents as those that do.
What about the Warlord you say. . . its brand new, how can it be one of the popular elements?
Well. . . the class is brand new, but we don't know enough to say that its playstyle is. Perhaps it turns out that its something that previously a fighter, paladin, or cleric build did well that is very popular. Under the new more narrow class focus, that play style gets its own class.
In addition adding some new elements to the game outside of what was previously considered "core" really reinforces the "freshness" of the new rules, so that it doesn't just feel like a overblown supplement or a 3.75 version.
All in all, I think they've done a good job and I'm looking forward to ditching my 3.5 Half-orc assassin in favor of a 4th edition Dwarven Fighter. . . or something.
