Don't think so. I have a feeling they will make Uncharted 3 and end it and make a new IP.
Also with Ratchet and Clank Future, Resistance and probably inFamous. Just looking at the past generations, Naughty Dog and Insomniac always made 3 games for each series that are within the story and also Sucker Punch with Sly Cooper.
Idk, just my feeling.