Great post, Jeff. Very thorough and detailed. Love reading your posts. Very informative.

I don't have any specific notification center ideas outside of the ones you propose.

My problem is, I'm building a WordPress Multisite network with WPMUDEV plugins and I need to make sure that all blog owners do not see WordPress updates in their individual site admins. Something I'm looking at and asking the WPMUDEV folks if they have a solution for it. It's not actually a problem just yet. Just anticipating it might be as I do more product dev on this project.