Sony has not 'officially' confirmed The Last Of US for PS4 but Sercan Sulun PlayStation’s Eurasian Software Market Manager has said while a sequel to The Last of Us may not be forthcoming any time soon, the first game will be released this summer for PS4 as a physical and digital copy, with enhanced graphics. He also mentioned that this version will include the DLC 'Left Behind
While Sulun did not say this in English IGN have had a professional translate this information and it is spot on.
And Sulun can be a trusted source as he has been wth Sony Since August 2012 and he is now in a pretty high position and sony has also said that they would like to make HD remakes of classic Playstation games on the PS4 so it is not an out in the blue suggestion. But this game was so well received with gamers and press that it would kind of be stupid not to do this.
And if you think that is not enough information, you might want to have a look at this, an English retailer has accidentally leaked The Last Of Us Complete Edition on PS4. And while i think that is probably real, I think the game should be The Game Of The Year edition because it did win game of the year, so they can make a copy like that.
While this all seems very real I just don't understand why Sony would do this, because Sony recently announced Playstation Now which lets you stream PS3 games to your PS4, and The Last Of Us was one of the main games that Sony showed off.