I think that more than any other movie I've seen, Garden State really managed to capture the feeling of being in your twenties when you're starting to do what you maybe, sort of, kind of want to do, and the disconnect between your everyday life and the life you once had at home.
The script was good; the dialogue was very natural, but I do think the third act was a little rushed. (Not that that stopped me from crying a little bit at the end...)