The last of us will most likely be there new IP but since they started working on it, they have expanded as a team (sony acknowledged their talent <3), so Uncharted will be their crown jewel. If The last of us us well recieved, then ND will be playing with that franchise and obviously Uncharted. If not, perhaps a new IP + uncharted. It all depends really on what they want to do with the last of us and how it turns out. One thing is for sure: Uncharted is Sony's flagship right alongside God of War and obviously Gran Turismo. Sony would rather die as a company than enter PS4 era without NDs Uncharted franchise. The insane acclaim and sales display enough interest from the fans and I dont think Sony even saw it coming themselves.
UC1 was good but UC2 and UC3 really took it to another level. Overall, the franchise being at 13M is easily putting a smile on Sonys face. Makes you think the money out in GGs engine for Killzone could have been used for ND instead xD. Luckily ND has 2 teams now meaning Sony did throw them some cash.
