On January 3, 2012, WordPress 3.3.1 was released to the public. This is a maintenance and security update.
For version 3.3.1, the database version (db_version in wp_options) remained at 19470.
To download WordPress 3.3.1, update automatically from the Dashboard > Updates menu in your site's admin area or visit http://wordpress.org/download/release-archive/.
For step-by-step instructions on installing and updating WordPress:
If you are new to WordPress, we recommend that you begin with the following:
From the announcement post: "This maintenance release fixes 15 issues with WordPress 3.3, as well as a fix for a cross-site scripting vulnerability that affected version 3.3. Thanks to Joshua H., Hoang T., Stefan Zimmerman, Chris K. and the Go Daddy security team for responsibly disclosing the bug to our security team."
A full log of the changes made for 3.3.1 can be found at http://core.trac.wordpress.org/changeset?new=19669%40branches%2F3.3&old=19590%40trunk
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