Pros:

Great for messing around and serious play.
Really fun to simply let loose with console commands.
Tanks can punch you off the stairs :D

Cons:

Needs a little more detail
Needs more weapons.
Tanks punch you off the stairs xD

Conclusion:

Very fun for sandbox play and messing around but also the occasional challenge :)

Pros:

Amazingly detailed map with lots of places to explore.
For the most part its true to the movie.
Really fun when you get up to the attic.
Overall well done.

Cons:

I can only think of two:
1.Most zombies don't come from the direction they do in the movie so the mines and the minigun facing that direction are pointless.
2.Its not on L4D2!

Conclusion:

I actually played this on l4d2 simply by putting the vpk in my l4d2 addons but it would be nice to have it officially added to L4d2. Great map, make the zombies come from the correct direction and it'l be perfect!

Pros:

The look of the map is amazing.
TONS of areas to explore.
Interesting horde events.
Challenging.
I love it.

Cons:

I really cant think of any other than there isn't another one yet ;)

Conclusion:

Its amazing 100 outa 100. More please.