The only meaningful thing to do when leveling in WoW for me is running dungeons. Questing is the painful thing you have to go through till you hit lvl 15. PvP is so unbalanced I struggle to believe Blizz hasn't done anything about it till now ... not even when they can see how TOR can handle it so superbly. So that's my PoV.
In WoW it's LFG->dung->LFG->dung->LFG. In GW2 it's exploring the world, completing all the events, visiting all the points of interest, collecting all the skill points and PvP that works. But there are ppl who like leveling in WoW. I like leveling in TOR, the main story that is, but it's really bad in WoW for me.