If you start a new game (replaying on "can i play, daddy pls?" instead of über for example), you keep every single collectible and perk.
Just a heads up.
Great, thanks - that's exactly what I wanted to hear!
They were teasing us with this:
And some bethesda employee while streaming the game said there are additional modes to unlock...
There are unlockable modes. You just have to... unlock them.