bartgraggI just used WPAU and it was soooo seamless it was scary! I had read posts where people were kvetching about all kinds of errors, etc., but I had NO problems, and my site and theme were customized before hand. I was a little worried.
Not a problem taking me from 2.5.1 to 2.6.2
http://wordpress.org/extend/plugins/wordpress-automatic-upgrade/
