Wordpress Automatic Upgrade plugin works
I just used the WP Automatic Upgrade plugin. Wordpress's upgrade procedure has always struck me as cumbersome, and this plugin makes the experience a lot simpler.
I ran into a few little snags, mostly because my Wordpress installation is not at the root of my server, and I have some rewrite rules that confuse things. But it was pretty robust to those problems, and I made it through the approximately 10 steps in the upgrade without having to go into a shell or manually do any backups or tar extracts.
IMO, the Wordpress team should work on nothing until this kind of functionality can be integrated into the main capabilities of Wordpress. PHP and PHP applications are such an extreme vulnerability, that all friction to keeping up to the latest patches should be removed.