Yeah, it's really out of tune. The first string he hits, i have no idea which one it is, but its the high one is pretty off. If you ask me, it doesnt matter, infact, it makes the song feel more generic and "real". Not overproduced and Justin Bieber-perfect. It's indie/punk-ish. It may be that weird guitar tom posted a picture of that is playing the intro and i dont think they are to easy to tune.