Tizen today reached a pretty big milestone in its life, as the Tizen 2.0 Magnolia software development kit (SDK) and source code were officially served up for download. This new release follows Tizen 1.0 Larkspur, which debuted in April 2012, and an alpha version of Tizen 2.0 that was released in September 2012. Interested developers will find a pretty lengthy list of changes in the official Tizen 2.0 release notes, but some of the more noteworthy changes that were highlighted on the Tizen blog include:

• Enhanced Web framework that provides state-of-the-art HTML5/W3C API support
• Web UI framework, including full-screen and multi-window support
• Additional Tizen device APIs, such as Bluetooth and NFC support, and access to the device’s calendar, call history, and messaging subsystems
• Web Runtime framework supporting new configuration elements for specifying the required features and privileges, and providing the basic runtime environment for NPRuntime plugins
• Native framework supporting full-featured application development and providing a variety of features such as background applications, IP Push, and TTS (Text-To-Speech)
• Core and native reference applications including Calendar, Contacts, Gallery, Phone, Settings, and Video Player
• Enhanced Web IDE providing WYSIWYG design environment, Chrome-based JavaScript inspector, and JavaScript log viewer
• Native IDE providing a project wizard, WYSIWYG design environment, unit test tool, and dynamic analyzer

As expected, most of that stuff will only really appeal to developers that are working with Tizen. There's also some meat to today's Tizen news for regular folks like you and me, though, as SamMobile took the time to load up the new Tizen 2.0 SDK and share some screenshots to give us all a peek at how the operating system is coming along. At the top of the screens, we can see a clock, signal strength indicator and a green bar that's likely related to the battery. The icons and switches shown in the screenshots are all very rounded, and the image of the browser app shows that there will be forward, back and reload keys up top and buttons for things like tabs and favorites at the bottom of the screen.

Tizen is an open source mobile platform that's been backed by companies such as Intel and Samsung and is managed by a Technical Steering Group. The OS is meant to run on several different kinds of devices, including smart TVs, tablets and smartphones, though no hardware that's meant for public use has been announced yet. That'll change later this year, as Samsung recently confirmed that it plans to release "new, competitive Tizen devices" sometime in 2013. No official details on the upcoming hardware have been spilled, but a handset with the model number "GT-I9300_TIZEN" was spotted earning Wi-Fi Alliance certification last year, which suggests that Samsung may be cooking up a Galaxy S III variant running Tizen. Good thing that we've got these screenshots and Tizen 2.0 release notes to keep us occupied while we wait for more information.

Via Tizen blog, Tizen 2.0 release notes, SamMobile