Dead Center
There is a special infected zombie who was named Jimmy Gibbs Zombie His poster adorns the malls wall.
On a CEDA truck in the campaign, it reads Disease Emergency Assessment Dispatch, which, ironically, spells DEAD, when using the first letter of each word.
There is a photo of a caged Boomer being held captive by CEDA in the first level of Dead Center in the first room on the right with the maps.
Swamp Fever
A Charger can be seen hung up by his extremities in the first chapter, Plank Country, of the Swamp Fever campaign. This is to take the shape of the "Lambda" easter egg, found in all Valve games.
Hard Rain
In the Safe Room where you collect the Diesel, there are remarks on the wall left by survivors named Chet & Erik. Chet faliszek and Erik Wolpaw are writers at Valve.
Like the original, but on the larger scale, L4D 2 features many Burger Tank signs and restaurants. Burger Tank if a reference to the Special Infected Tank.
The Parish
The Jukebox in the corner-shop of The Parish plays Still Alive by Jonathon Coulton when fiddled with enough. (Another Jukebox can be found Swamp Fever, which plays the same songs. Both of these also play 'Re: Your Brains', another song by Coulton. When this song reaches it's chorus, it summons a horde.)
The Bus Stop signs of The Parish have the word 'PWN' on them.
'Gnome Chompksi' is a play on the spelling of the philosopher Noam Chomsky.
Like in the original, it is possible to find a dead immune teenage girl, the only person in the game under 18.
Characters
Ellis has his own Facebook Page and Youtube channel
The Midnight Riders also have a Youtube Channel, and they have their own website
Weird Stuff.....
WTF parish campaign ? Edit fake
VIRGIL DUGAS 1953-2009
Grafiti found in The Shantytown: Virgil is the pilot of the boat that helps out our survivors. This suggests that Virgil ran away from the Shantytown, knowing that they could not stop the infected.
A human with the initials KP appears in grafiti in both Left 4 Dead and Left 4 Dead 2.
Companion Cube ?
PWN on the side of the nade luncher
A reference to Bill and Louis ?
fragment of newspaper in first room of DeC that says the Midnight Riders Tour has been canceled.
Non zombie dead girl in Dark Carnival 1
Far corner room of motel.
Source from steam forums and tacticalgamer
