Pros:

-Great combination of my two favourite games
-Intense panic events
-No tanks until the end
-Great application of TF2 sounds and music
-Ellis' reference to TF2
-Melee weapons on the cart (great idea, but they need to be outlined)
-Good variety of infected
-No witches
-Challenging

Cons:

-The survivors said "the helicopter's arrived!" when I sitll had 4 more gas cans to pour in
-Coach said "The Midnight Riders saved us!" which had little to no relevance in this campaign
-I didn't get to the finale because the bots all died

Conclusion:

All in all, a fun map. I love TF2 and I love L4D2, so obviously I loved this. It took me aaages to figure out how to get to the last 4 cans (up the numerous flights of stairs next to the hole) but that was probably just me being stupid :P
Very innovative, fun to play, but the bots let me down towards the end (not a problem with what you did, just stupid AI).

Anyway, job well done. Especially since this isn't a finished release.