Wordpress 3.9 beta 1 is now available for download and testing.
new paste handling
added widget management to customizer
added the ability to upload, crop, and manage header images, without needing to leave the customizer.
new theme installer.
Galleries now receive a live preview in the editor.
now drag-and-drop images directly onto the editor to upload them.
improved editing images.
New audio/video playlists.
Download WordPress 3.9 Beta 1