The Joomla project has announced the immediate availability of two Joomla releases:
These are both security releases, and site administrators should look to upgrade as soon as practical.
Note that most users should update their sites to version 2.5.1 instead, which is now released. Version 1.7.5 is only intended for those users who for some reason are unable to update to version 2.5.1. Version 1.7 will reach end of life on 24 February 2012.

