Yes it means that you will find pieces of gear for all slots just by playing the game (questing, killing regular monsters, etc.).
However, if you want to get Epic Shoulders, you will need to take on Elites and Dungeon Bosses.
So that way we know that everyone generally speaking should get geared up, but then those doing the most difficult content are going to be getting that extra-special gear that goes above and beyond the base level.
I think we will definitely see that, in fact what may end up happening is that there is a "Class Item" slot that determines the shield cosmetic for warrior, the wand casting line for runemage, the turret of the musketeer, and the trap of the archer, or something like that. We just haven't had time to do it yet.