One important element in warhammer is how your not stuck in a linear path in terms of what your doing. For example, I don't know if they changed it since, but in WOW you either PVP'ed, or you quested out in the world. You had to stop questing, head all the way into the heart of a city and sit around waiting on a battle que.
In warhammer, you can have your thumb in a few pies at once. You can be questing around, but have set yourself into a PVP battle ground que from any point (even from the very moment you start playing a new character, actually). It'll pop you into the scenario once its ready, then put you right back afterward. That way if you want to do PVP, questing is something you can work on in between scenarios rather than being a big one or the other, not both situation.
To me, the low level PVE questing is much the same as other mmorpgs - somewhat interesting, but if it's the only thing your doing, the shine wears off quickly. However, if your breaking it up with an occasional intense PVP scenario, the questing doesn't drag on an keeps it's shine. Or if your enjoying the questing just for its own sake, don't turn on the scenario que. It's up to you and you shape how you play, rather than being stuck in the way some developer decided to go.
That and you can dip into public quests as well while on the way to your normal quests, which you were doing while you were waiting on the scenario que - you genuinely choose how you have fun and in a way that doesn't hurt your progression (sure in other mmorpgs you might have freedom to explore, but generally it hurts your numbers progression - and if that doesn't matter to you, then 95% of mmorpgs don't matter to you).
I'm done - go play! :)