A source that has been able to lay hands on an early boxed copy of Destiny from Bungie and was surprised to find that the install requires 40GB of hard drive space for the Xbox One version.
That being said, it is interesting to see that the Destiny pre-load is only 19GB so far. Could this be a hint that a massive day one patch is coming for the pre-load digital version? In most cases the retail boxed copy and the digital download version are the same size or very close.
Difficult to say what might be up with this, but these days day one patches are not at all uncommon. Given that fact, we have to guess that the pre-load isn’t yet finished and there is more to come before release day.