An explanation of some of the meme imagery.
This review's purpose is to inform viewers about the various meme images shown in the video. I'll start from the top:
Moot: Moot is the webmaster and administrator of 4chan. he often represents himself as that little cat in a dress.
WT girl: represents WTSnacks, a moderator at 4chan. Moot fired him recently, prompting a meme of "BRING BACK SNACKS". the large golden hammer is the Banhammer(or B&Hammer).
Green haired girl: Yotsuba(4 leaves in japanese). her distinctive green hair represents toe image of 4 leaves used in 4chan's logo.
black van with 4 guys in it: the 4chan party van. this is commonly used to refer to the FBI. the 4 guys are actually some staffers at IGN. their reactions to something have become a meme.
smiley guy: the cockmongler. he is a very old meme, and has been around for years. the other monglers running beside him have the faces of Gendo Ikari(Neon Genesis Evangelion) and Koffing(pokemon)
Sage and Age: represent the sage and age commands on 4chan. by putting sage into the email field of a post. you will not bump a topic by posting. age has no actual effect, to the best of my knowledge.
furries: 4chan does not like furries.
cats: 4chan does like cats. a lot. many memes feature cats.
steamroller guy: WRYYYYYYY. originally from a japanese flash showing the super moves from jojo's bizarre adventure. the character Dio Brando attacks by crushing the enemy with a steamroller in one move, while screaming WRYYYYYYYYYYY.
notes: despite being called 4chan city, this flash is based entirely on 4chan's /b/ board. /b/ is one of the most active boards on the entire internet, with nearly 9 million posts to date. it is also damn near entirely free of rules, with the exception of the NO KIDDIE PORN rule, which is universal to all places. also, you can be banned for being a god damn moron as well.