Naughty Dog have never missed a release date. Ever
That doesn't stop them from being able to delay the game. Personaly though, if the game is not ready don't rush it like Uncharted 3: Drake's Deception, delay the game please.
oh they did rush UC3 and it wasn't great as uncharted 2 was especially with UC3 multiplayer what a mess it became COD wich killed it 4 me. if they end up delaying it it better not be more then 2 months.