WordPress 3.9 will feature the updated TinyMCE version 4 in core when it’s shipped next month.
Version 4 looks real nice. It’s got a completely new GUI, simple and faster dialogs, and new and improved APIs and default plugins and better code quality.
It’s also minimalistic. Buttons have been dumped for WordPress, such as the paste from Microsoft Word button (who uses that, anyway?). There are just 14 buttons.
What a lot of WordPress users don’t realize, though, is that there’s more to the WordPress Visual Editor – and its backend, TinyMCE – than meets the eye.