Friday afternoon marked the release of Ubuntu 12.04.3 LTS, the latest point release to the most recent Ubuntu Linux Long-Term Support update.
Ubuntu 12.04.3 LTS includes various updates that were released post-12.04 (and 12.04.2 for that matter) mainly focusing upon security and other pressing issues. The 12.04.3 LTS update, of course, maintains compatibility with earlier 12.04 point releases.
Kubuntu, Edubuntu, Mythbuntu, and Ubuntu Studio have also been updated to the 12.04.3 LTS status for those not wishing to use the latest 13.04 stable release or the 13.10 daily development images.
More details on the Ubuntu 12.04.3 LTS release can be found via the mailing list announcement