Pros:

The map is fantastically designed, I love the way that the map guides the player through using light and colour in a subtle way, especially in a dark map like this.
Very Unique scenarios such as the baby crying gave the map a very creepy atmosphere.
Smart placement of weapons
Smart placement of mini guns, allowing sort of an overwatch position 
Custom music, models and sounds add a unique touch and the voice acting is solid
The Bots acted intelligently 

Cons:

As everyone has said the catacombs are a bit confusing
The finale cut scene was very lacking 
The lack of survivor conversations was disappointing, they said what they needed to say but didn't interact 

Conclusion:

This map is worthy of its score and ranking, its one of those special campaigns that has unique ideas and a consistant atmosphere and doesn't go completely overboard with stupidity.This is an essential map and it will probably stay on my PC for a while