Yup, you pretty much have to play the game on Hard the first time through. I really regret going through it on Normal the first time, was almost no point where I didn't feel like I had more than enough ammo and resources. On Hard you felt much more desperate, but not to the point where it was unbalanced. Still haven't tried it on Survivor or Grounded, but I figure those must be pretty crazy.
Oh and Puddy, though the gameplay doesn't change super drastically as such, then it starts off amazingly with the prologue, but then takes dive for the next 2'ish hours, but when it finally gets going again then it pretty much doesn't let go.
Anyway, saw the Last of Us Live thing yesterday, was way better than I expected and that PR bullshit must've worked because now I'm all ready to double dip (or triple dip?) and give it another go on the PS4.