In reply to Daniel.

There's an answer to your question, I just don't know it or it hasn't been developed yet. There's a way, but it's not in core today. I've heard from the people loud and clear, that today is not the day to turn it on for everything. There's a long road to travel. I saw some stats and figured if people can't be pressed to keep their plugins up to date, then all hope is lost and it's time for WordPress.org to do it for them. But, thanks to the conversations here, I've changed my tune a bit for now. For example, one of the obvious questions brought up is "What problem does running the latest version or newest code actually solve?" Nothing obvious that I can think of, but then, why do we educate users to keep things up to date as a security precaution?

At any rate, I think at some point down the road, whether we like it or not, new installs of WordPress will have auto updates for everything turned on. The way it's looking, it'll be a few years at least.