I installed WordPress 4.0 and found these 11 new features after the official version "Benny" was released.
Codex: http://codex.wordpress.org/Version_4.0
Some features are new, some are brought back from the previous versions, like the custom color in color picker.
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0:21 1. Language option before installation process. Note, you will only have this when you install manually. Check out my video how to do this: • Install WordPress 4 or 4+ Manually in cPanel
1:22 2. Site Language in Settings - General. You won't have this in your site, if you never installed WP in other languages.
1:57 3. Grid View on "Media" and "Bulk Edit" button, as well as easier navigation from one image to another.
2:57 4. New "Add New" Plugin look or appearance.
3:36 5. "More Details" of a plugin now has a new look too.
4:15 6. Sticky post editor "toolbar" and "1 or 2 Scrollbars" option.
6:43 7. Widget new look in "Customizer" of a theme.
7:28 8. Oembed Embed on "Visual" tab now has the visual preview.
8:34 9. Visual preview for any Oembed media on "Add Media" - "Insert from URL"
9:02 10. Easier navigation previewing theme with arrows.
10:13 11. Custom color for color picker in your post editor is now back. It was there, and then removed in previous version, and now it's there again.
whats new wordpress 4.0
what's new wordpress 4.0
wordpress 4.0 new features