I don't actually buy that they didn't plan to ship with the camera originally. Why else would they preload the camera demo stuff on the PS4, which was one of the first things they should about the console.
No, I'm convinced they watched MS walk into a meat grinder and rapidly changed their minds, which also allowed them a very nice price point.
Preloaded games/software that require the camera on every PS4 as well as a nightlight on every single dualshock 4 controller. I don't think there's any question they intended to do it. Fortunately they didn't.