The Zen of updating Wordpresswordpress
Wordpress automatic updates never work.
No matter if it's a major version change or just a small bump (let's say… 3.0.4 to 3.0.5, uh?), I always end up downloading the whole thing and updating it manually because the update page stops responding and plainly goes blank.
Instructions for update are here, by the way. And after the steps to update, they include that little snippet of wisdom:
How could anyone be angry at Wordpress after that?