Yeah, off on what Jed, I think, said, Sal is totally lost. He really doesnt belong anywhere and he wants to be everybody else- all levels of life etc. He's also totally fickle, which tends to be really annoying.

Also, the whole plotline is very Holden-esque, as many people have earlier noted, but it seems like Sal has no personality, very much unlike Holden. You know what I mean? Sal tries so hard to be like everybody else, and you end up with this personality free guy.