My wife and I haven't had kids yet (we're hoping to start that journey in about a year), but we've discussed this topic a bit. She's a mother/baby nurse, and she sees both sides.
AD--It is more "exciting" post-delivery because of the surprise.
BD--Better for planning, apparently. Embroidered blankets, hats, shirts, etc. with the baby's name; planning a nursery at home (color, decorations).
I couldn't have made this post without her input, by the way.