I was watching the following video on WordPress TV recently where Matt Mullenweg was discussing the problem of upgrading WordPress and then plugins breaking your site:
It was mentioned, which is certainly the case for me and my clients that there is a lot of fear when pressing the auto upgrade button in case things break, such as plugins breaking on a newer version of WordPress.
With this in mind it struck me that to go some way to solving this problem, could the auto upgrade not behave in a similar way to the theme preview in the appearance tab.
When testing a new theme you are able to press 'Preview' rather than activate and then see if the theme meets your needs. You can click around and check that everything is to your liking before committing to the theme on your live site.
Could something similar not be used for upgrades. Here is how I envisage this, although I must confess I wouldn't know were to start in implementing it:
You click upgrade as you would normally and then WordPress downloads its stuff etc. Then your site appears in a 'Preview' lightbox type thing like in theme preview, where you can then click around and make sure that nothing has been broken. From here you could then press a 'Commit to live site' button or you could press a 'Don't upgrade live site' button if something was not working as it should.
Could this actually be implemented? I am not sure, but it would certainly help in removing the fear with pressing the auto upgrade button!