The exploration in GW2 actually really disappointed me, because it's all planned out for you.
Although as you point out, it's better than exploration was in WoW if you exclude areas you weren't supposed to be able to get to at all.
Of course, for me that's where the real exploration was in WoW. Old Ironforge, CoT during vanilla, finding an exploit that let us get all the way to the edge of the world, Mount Hyjal during vanilla.. it's been years, and I still distinctly remember doing all those things, how I did them, and who I did them with. Nothing memorable about exploring in GW2 for me.