'The Daily Show' - May 10, 2010 - "Clustershag to 10 Downing: Hung Parliament" excerpt
"So while the [British] election itself was a bit of a disappointment, the coverage was fascinating and top shelf. The BBC took one correspondent and planted him into a virtual world by digitally rendering hundreds of members of parliament all around him before blasting lasers through their heads. Having completed level one, they took the same reporter and transported him to a virtual staircase inside an M.C. Escher drawing where he correctly named several past prime ministers. And then onto the boss level, where he was forced to build a Magneto-style walkway that he used to approach and enter the famed 10 Downing Street, where once he was there he encountered -- ZOMBIES! Nooo! It was a trap! Noo! Nooooo! ... You should have never unlocked the door on level two!"
'The Colbert Report' - June 28, 2010 - "Doomsday Bunkers" excerpt
"Folks, when the end of the world comes, make sure you have a spot in a Vivos bunker... if you want to die! [...] Because I have uncovered an even ancienter, Summerianer tablet predicting Armageddon within the Vivos bunkers. That's why the Prescott Group has designed an exclusive, highly secure, under-the-bunker bunker where you and your family can safely retreat in the event of an intrabunker Armageddon. For just 1.2 million dollars, you'll be spared the chaos in the bunker above while enjoying such amenities as corridors, handguns, and a very attentive zombie staff. Act now before it's too late."
Not entirely sure from which game (at least I'm assuming that it's a game) 'The Daily Show' borrowed the CGI zombies. However, 'The Colbert Report's footage is most definitely from the Left 4 Dead games. If someone should let me know about the former, I'll be sure to amend this post.
Better Know A Stephen: Stephen King