Looks like Atto has been selected to be Moodle’s default text editor from 2.7’s release on. The text editor, specifically built for Moodle is written in javascript as a standard Moodle YUI module. You can already give it a try by logging into http://prototype.moodle.net/editor/.
Follow the discussion at https://moodle.org/mod/forum/discuss.php?d=245896#p1100563 (link updated)
And be sure to chime in on the features that are essential to you as a teacher/administrator.
You can learn more about Atto and how to develop sub-plugins for the text editor at http://docs.moodle.org/dev/Atto
