has a more information about the game's set-up/scenerio straight from Naughty Dog (I've bolded the info that seems most interesting):
'The Last of Us' is Naughty Dog's next chapter
By Mike Snider, USA TODAY
Updated 15h 7m ago
Sony Computer Entertainment America
It all started with a fungus.
In 'The Last of Us,' main character Joel and his teenage companion, Ellie, must fend off zombie-like mutated humans.
A spore of an idea from the Planet Earth documentary series is growing into a new video game from Naughty Dog, the studio behind the PlayStation 3's flagship Uncharted franchise. The Sony-owned studio's recent release, Uncharted 3: Drake's Deception, is nominated for multiple game-of-the-year awards.
This new project, The Last of Us, involves a virulent fungus that spreads through the human population in the near future. That leaves the unaffected in a constant battle for survival.
In the first trailer for the game, shown during Saturday's Spike TV Video Game Awards broadcast, a middle-aged man and a teenage girl are attacked by zombie-like mutated humans. "This is our routine. Day and night," says the girl character, Ellie, in a voice-over. "All we do is survive. It never lets up."
Expected for PS3 in late 2012 or early 2013, The Last of Us is a rare new intellectual property in an era when publishers rely heavily on trusted franchises. "The team at Naughty Dog is known for incredible storytelling, and what excites me most about The Last of Us is the potential of a grittier and more mature story," says Geoff Keighley of Spike's GameTrailers TV. "If Uncharted is the video-game version of Indiana Jones, The Last of Us has the potential to be a video-game version of Cormac McCarthy's The Road."
Although the designers don't want to give away the entire story line, the development team recently gave an exclusive inside look into the project. At the start of the game, the lead character, Joel, finds Ellie, and they team up. Joel is "a vicious survivor. When he meets this girl, she is his one chance at redemption," says Neil Druckmann, the game's creative director. "That kind of arc has always been intriguing."
Back in 2008, Druckmann had been mulling an idea for a graphic novel about a father and daughter in a zombie tale. He and game director Bruce Straley were watching the BBC/Discovery series Planet Earth and saw a segment on the cordyceps fungus. At the time, both were working on Uncharted 2: Among Thieves; they had also worked on Uncharted: Drake's Fortune.
In close-ups, the documentary showed how the parasitic fungus infected ants and, having taken over their brains, resulted in protruding growths from their heads. A thousand-plus fungus variations exist, each genetically targeting an individual species. "We instantly thought 'humans,' " Straley says.
The two discussed how "it would be a cool realistic backsetting to a zombie movie where this thing jumped species," Druckmann recalls, "not knowing there was going to be another (game) project."
Meanwhile, Naughty Dog co-presidents Evan Wells and Christophe Balestra had been considering splitting the one-project-at-a-time studio into two teams. "We felt if we didn't expand the roles for people, we could potentially lose them, because they really wanted to be challenged," Wells says. "We didn't want to lose that talent."
So after Uncharted 2 shipped, some studio members moved to the Last of Us project, while others worked on Uncharted 3.
Like the Uncharted games, The Last of Us has a third-person perspective, in which you see the character on-screen, but it has a more realistic, cinematic look. "We're trying to move the medium of video games into an area elevated in the same manner of respect of film," Balestra says. "We want to redefine what our medium is even called. 'Video game' is not an accurate name anymore. It is not necessarily a game with rules and a winner and a loser. It's an experience."