I read somewhere that I can set a constant in the wp-config.php to update WordPress from the latest trunk version and not the stable version.
Stupid as I am, I can’t find the site anymore where it was written.
I know I could also update with SVN, but I thought the autoupdater was a smarter version.
http://wordpress.org/extend/plugins/wordpress-beta-tester/
Sets you up for the nightlies, if that is what you are looking for. I’ve got it running on my dev install @ cdn.rvoodoo.com. Works great there
There is no config setting or definition you can set that will automatically update WordPress.
Your options are to use the Beta Tester plugin, manually update, or do an svn up.
You could set up a cron job on your server to run the svn up command every 12 or 24 hours but if there is a database upgrade you will still have to manually push the “upgrade database” button.