As for Amy's Bread Monkey Cake vs. Hummingbird Cake, well...
Monkey Cake has walnuts. Hummingbird Cake has pecans. (That one recipe stating that either one works and that they taste the same... Umm.. No.
) Hummingbird Cake tends to be a bit more "spicier" in my experience. Magnolia Bakery will sometimes feature Hummingbird Cake and/or Hummingbird Cake Cupcakes, and it's definitely different from Amy's Bread Monkey Cake. Just sayin'...