And i don't feel like we know each other amazingly well, not like say my best friend in high school whom i had known since kindergarten. (How important is it to know someone's history? i wonder. I mean, it's interesting, but i wonder how important it is to understand a person, to "know" a person.) We don't have the shared history, but we're pretty up-to-date with the day-to-day (thanks to LiveJournal and living in the same house thereby seeing each other frequently). And i'm sure there's plenty about our personalities, belief systems, whatever, that we don't know about each other, but it's weird to have to ask, to think "what would be interesting/useful/informative/whatever to know about this person?"
And then i wonder how much of this is just true of friendships in general, how you know the surface daily stuff, but you don't learn the other stuff except when it comes up, so shared history is important that way, in that it is only as your shared history develops that you learn these things.