Pros:

*  Loved the train part
*  Great Layout
*  Nice transitions

Cons:

* Dont play with bots
- They tend to get stuck a lot
- They have trouble going in the truck saferoom
* Map 3:  Fall off of the side building stairwell easily

Conclusion:

Great Campaign!  Just dont play in L4D2 though, like I did on my first play through. :p