It doesn't come as a big surprise that a super successful game would get developers thinking about a sequel. [url=http://www.eurogamer.net/articles/2014-02-07-naughty-dog-mulls-the-last-of-us-2]Naughty Dog has been thinking about a choice between a new IP or a TLoU sequel.[/url] Do you want to see more of The Last(ish) of Us, or would you rather see what else Naughty Dog can do?
Note that wondering what a naughty dog can do does not mean the same thing in other contexts.
There should be games that have stories that branch into sequels, like the Halo series, and games that just be stand alone titles, like Journey. I think The Last of Us would be best as a stand alone game, but a sequel could have lots of potential. Valve as this problem with Half Life 3. They have so much hype and such a good game to live up to that they don't want to disappoint everyone. [spoiler]For mentioning Flappy Bird, I will devour your soul and the souls of all you hold dear.[/spoiler]