I just updated this blog to WordPress 3.1 and it is really nice. The update was smooth and I had no problems. One of the coolest things is the new admin bar. This bar is similar to the bar that you see on WordPress.com sites but now it is on self-hosted sites. It really adds something to your browsing experience and managing your blog.
If you have WordPress, make sure you update to the latest version. If you are using something different, consider moving over to WordPress. It's a great platform.