WP_Comment_Query and WP_User_Query
classes now support meta queries just like WP_Query.
Meta queries now support querying for objects without a particular meta key.' ); ?>
WP_Post class, which improves performance by loading selected properties on demand.' ); ?>
WP_Image_Editor class abstracts image editing functionality such as cropping and scaling, and uses ImageMagick when available.' ); ?>
switch_to_blog() is now significantly faster and more reliable.' ); ?>
WordPress API is now always enabled, and supports fetching users, editing profiles, managing post revisions, and searching posts.' ), __( 'http://codex.wordpress.org/XML-RPC_WordPress_API' ) ); ?>
Underscore and Backbone JavaScript libraries. TinyMCE, jQuery, jQuery UI, and SimplePie have all been updated to the latest versions.' ), 'http://underscorejs.org/', 'http://backbonejs.org/' ); ?>