MLEB 2013.01 has been released by Amir Aharoni. Lots of development has been happening in Translate due to the work on the new translation interfaces. If you are a developer, please also checkout the latest new and changed Web APIs and give us a shout in #mediawiki-i18n @freenode if you see something obviously wrong or missing. Also included in this release are bug fixes for Universal Language Selector, while the other included extensions didn’t see many changes.
Some months ago I wrote about Language tag validation in MediaWiki. A nice person named Siebrand Mazeland decided to improve the situation. As of now we have three new methods developed by the Wikimedia Language engineering team:
Unless these methods are backported to MediaWiki 1.19 and MediaWiki 1.20, it will take a while before these are being used in extensions, but after a while we should see faster and more readable code.