Forget the Disney version--I'm talking about the original text by A. A. Milne and the illustrations by Ernest H. Shepherd. I recently found a copy of the complete stories in my house, and I think that it's a great resource for us.
1. Narration/story telling in a way that refuses to talk down to children.
The general premise is that the narrator (Milne) is the father of Christopher Robin (his kid IRL!) and is telling him the stories that Christopher Robin has had with his stuffed animal/real animal friends. It's not a parent telling bedtime stories to his child, but more someone remembering stories to another. There's an equality in the power dynamics between the two.
2. A whimsical world that follows its own internal logic system.
Milne creates this forest world where all his characters dwell, but there is a blend of elements taken from the real world and from the imagination. While it's accepted and unexplained where the kangeroos came from, or how certain laws of physics are defied, Milne is consistent with his descriptions of the world he has created and with the personalities of his characters. There's a balance of suspension of belief and conviction in representation. I guess what I'm saying is that we can do whatever we want, but we need certain elements or rules that remain constant. We need to make a logic system to abide by so the world we create makes sense within itself.
3. The illustrations!
There's a simplification of form made with this great line work, where there's this controlled and frenetic mark making happening at the same time. In the later versions where the illustrations are colored, the line work isn't as busy, but the colors! So nice. To me the colors say natural but whimsical, playful and youthful.
Sorry for such a long megapost, but I can bring the book with me to Richmond if you guys want to see it firsthand. The pictures here are from the internet, but the ones in the book are better quality.