WordPress 3.1.1 might not bring any new functionality to the popular content management tool, but it does fix a number of bugs and potential security issues.Self-hosted WordPress users, fire up your update engines because WordPress 3.1.1 is now available.
New changes has announced by the WordPress team on the official WordPress blog:
Some security hardening to media uploads
Fixes for IIS6 support
Fixes for taxonomy and PATHINFO (/index.php/) permalinks
Fixes for various query and taxonomy edge cases that caused some plugin compatibility issues
Users can download this new update from WordPress.org/download.