Pros:

Great Atmosphere
Sound lighting
All really good textures used in the map
The multiple levels are pulled of nicely
Some really great spots to take on the infected

Cons:

A few bugs here and there but nothing crippling to game-play

Conclusion:

A realy good map and pays great homage to the original. With a great atmosphere and large amounts of space it can lead to a good amount of tension.  A great map that shines as one of the best that I've played in a long time.