Indeed. Even spoilered beyond all belief, this anime still hit me hard...my soul would have been destroyed after episodes 3, 8, 9, 10, and 11. The build up to 12 made it all worth it though.
The whole thing was just beautiful.
~WARNING! MIND AT WORK!~
KH Wiki: The Keyhole
Fairly solid as a resource and rather organized, perfect for newcomers to KH.
Kingdom Hearts Wiki
Parent-site of The Keyhole, a little less organized in my opinion, but goes a little deeper into the mechanics of KH.