Doesn't one lead to the other? What's the technical difference between allowing person to touch the same document on 4 devices, and two people touching the same document on 6 devices?
I don't know what the technical differences are, but I'm not sure how that's relevant. My point is, Apple doesn't seem to be interested in enabling that. And I'm not necessarily talking about collaboration, but even just sharing. Apple has given me great ways to take, edit, store, and organize my photos, but my primary purpose for all of that is to show my photos to others. They seem to have ignored that part.
If you're implying that that's the obvious next step for them, then, great, I hope that's the case. But the only time as far as I can remember that they even made gestures toward addressing this was Ping, which was an unmitigated disaster.
Perhaps I'm missing something, but isn't the system-wide Twitter integration addressing exactly the point you are talking about? I'm not saying this means they shouldn't be doing more, but I don't think saying they aren't doing anything on this front is correct either. iPhoto on the mac also got Facebook integration recently (though I find it to be buggy).
I also missed collaboration and sharing capabilities but Apple likes to take one step at a time. They are too good at this to just overlook collaboration and sharing, the only problem might be that implementing it could take them quite some time.
