Most people are probably going go crazy because version 2.5 literally just came out a couple months ago. But as I mentioned back in June: it is not as heavy of an update this time. However, that is not to say it isn't feature-rich! It's full of goodies, like the "post revisions" view that lets you compare changes as you write/edit blog posts:
Don't be afraid to upgrade. It did not break any of my plugins or my design and it really isn't that intensive to do. Here is a quick guide, even shorter than WP's famous "5-minute install" guide:
- Download the latest version of Wordpress.
- Backup the following:
- Your WP database. (Jem explains one way.)
- The /wp-content/ directory.
- The /wp-includes/images/smilies/ directory (if you have custom smilies).
- Your wp-config.php file, located in the root of your WP installation.
- Delete the folders wp-admin and wp-includes. This won't kill your site, seriously! You're going to add those directories back anyway. Don't panic!
- Copy over all the new files from the download into your WP directory, except for wp-content. You want to keep your themes and plugins, yes?
- Copy back over your smilies, if you had custom ones.
- Go to your WP admin, click the "upgrade" button and poof, you're done.
Don't be afraid you will lose anything or mess up your site. As long as you back up your posts and wp-content folder, you are fine if anything actually does happen.
There is really nothing you can do to break your Wordpress website unless you were purposefully trying to. 
Not saying the upgrading process is fool proof, but I've rarely had problems in my experience. Make sure you take the time to upgrade, as new versions usually equal better security and more useful features.
I’ve not had problems before but your install guide is very handy. It sounds a lot less daunting than the essay WordPress wrote. 
Hehe, glad the mini-guide is helping some of you!