Felt like adding a new thread for little fun facts or other things you noticed or questions you've always wanted to ask.
Previous threads
http://forum.square-enix.com/ffxi/threads/12313-The-Mysteries-of-Vana-Diel
http://forum.square-enix.com/ffxi/threads/7057-The-little-things-in-the-game-Spoilers
As far as new things, something I noticed while working towards the final fight in ACP is that unlike a lot of other Final Fantasy games, the crystals themselves seem to be working against us. While their light is typically seen as a good thing and they do sustain the world, it was their will that led to Eald'Narche deciding to reunite the mothercrystals and destroy Vana'diel. Their holy warriors appose you and even a small version of the main crystal or something like that tries to do the same thing.
Additionally, unless I'm mistaken, the crystals that we are most familiar with for synthesis are actually formed from the emptiness inside the mobs we fight, which is wierd as the emptiness itself has qualities that remind me more of the Void, which the light of the crystals banishes. I guess in essence that would make them dark crystals? Additionally in the final battle for CoP and Apocalypse Nigh we see the emptyness used as a weapon for our side, which is also really odd.