BlogsWeek.com

WordPress release 2.0.3 is available for download. “This is a bug fix and security release, and is recommended for all WordPress users. In addition to an issue that was raised on Bugtraq a few days ago, we’ve also backported a number of security enhancements from 2.1 to further enhance and protect your blog.
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Upgrading is fairly simple, just overwrite your old files with the latest from the download. When you go to your admin it will give you a link to update your database.”

For further details, please read the full WordPress 2.0.3 release announcement.