When a new wordpress version is released you'll probably find out about it sooner then it will be available for automatic installation in your wordpress admin.
This is because wordpress checks for new versions twice a day,but the check is scheduled based on the time when you installed wordpress so unless you're lucky you'll have to wait for up to 12 hours before the update shows up in your wordpress admin and use it.
This gave me the idea that it would be nice if you could check manually as soon as you find out about the upgrade, so I created this plugin that just gives you a button that you click and it will check to see if there's an update available right away. If it finds on it shows you the upgrade link.
Download: WP Version Check-0.1 (95.2 KB)
To check for an update go to wordpress admin -> Tools -> Version Check