* Framework changes
  * Added dependency injection of framework capability
    * Adopted Zend\Di component of Zend Framework 2 library
    * Implemented object manager in Magento application
    * Refactored multiple base classes to dependency injection principle (dependencies are declared in constructor)
  * Themes/View
    * Implemented storing themes registry in database, basic CRUD of themes, automatic registration of themes in database from file system out of the box
    * Renamed `Mage_Core_Model_Layout_Update` into `Mage_Core_Model_Layout_Merge`, the former becomes an entity domain model. Similar changes with `Mage_Core_Model_Resource_Layout` -> `Mage_Core_Model_Resource_Layout_Update`, `Mage_Core_Model_Layout_Data` -> `Mage_Core_Model_Layout_Update`
* Performance tests
  * Improved indexers running script `dev/shell/indexer.php` to return appropriate exit code upon success/failure
  * Implemented running the same performance scenario file with different parameters
  * Slightly refactored framework class `Magento_Performance_Testsuite_Optimizer` for better visibility of algorithm
* Visual design editor
  * Added ability to remove elements in editor UI
  * Revised history of changes VDE toolbar and algorithm of "compacting" operations (moving, removing elements) as a layout update XML
  * Added selection of themes to VDE launcher page
* Refactored JavaScript of some UI elements to jQuery:
  * "Simple" and "configurable" product view pages
  * "Create Account" page
  * "Shopping Cart" page
  * CAPTCHA
  * Newsletter subscription
* Tax management UX improvements
  * Split Basic and Advanced Settings for Tax Rule Management UI
  * Moved the Import/Export functionality to Tax Rate page
  * Moved Tax menu to System from Sales
* Implemented the editable multiselect JavaScript component
* Added mentioning sitemap in `robots.txt` after generation
* Removed creation of DB backup in integration testing framework
* Fixed logic of order of loading ACL resources in backend
* Fixed JavaScript error during installation when one of files in `pub/media` is not writable
* Fixed structure of legacy test fixtures that allowed ambiguous keys in declaration
* Fixed inability to restore admin password when CAPTCHA is enabled
* Various minor UX fixes (labels, buttons, redirects, etc...)
* GitHub requests:
  * [#59](https://github.com/magento/magento2/issues/59) -- implemented handling of unexpected situations in admin/dashboard/tunnel action
  * [#66](https://github.com/magento/magento2/issues/66)
    * refactored ImageMagick adapter unit test to avoid system operation
    * simplified unit testing framework -- removed unused classes, simplified handling logic of directory `dev/tests/unit/tmp` and removed it from VCS
  * [#73](https://github.com/magento/magento2/pull/73), [#74](https://github.com/magento/magento2/pull/74) -- fixes in docblock tags
  * [#75](https://github.com/magento/magento2/pull/75), [#96](https://github.com/magento/magento2/pull/96) -- fixed translation module contexts in a few places
  * [#80](https://github.com/magento/magento2/issues/80) -- fixed some runtime errors in import/export module
  * [#81](https://github.com/magento/magento2/issues/81) -- removed usage of "remove" directive in places where it is overridden by setting root template anyway
  * [#87](https://github.com/magento/magento2/issues/87) -- changed paths of files to include from relative into absolute in `dev/shell/indexer.php` and `log.php`
  * [#88](https://github.com/magento/magento2/issues/88) -- provided comments for values that can be configured in `app/etc/local.xml` file
  * [#90](https://github.com/magento/magento2/issues/90) -- slightly optimized logic of implementation of loading configurable product attributes