It seems that the journal can't be dropped now. When attempting to drop it, it says "You're wielding that, take it off first." Using it (like one would to unequip something else) doesn't work for obvious reasons. It doesn't have an * next to it in the inventory either like other equipped items.
Personally, I prefer to drop it to save two pounds, since it's almost always an easy trip back to the bunker when humanity drops too low.