Automattic

Andrew Ozz

Nikolay Bachiyski

Ice allows you to visually distinguish who changed what in the post content and then approve or cancel those changes.
Ice Visual Revisions is based on the <a href="https://github.com/NYTimes/ice" rel="nofollow ugc">Ice library</a> developed by The New York Times CMS Group.

Ice Visual Revisions

Adds revision tracking to the visual editor. Modified, added, or deleted text is shown in color, along with the user and time of change.

Ben Balter

One-click implementation of the <a href="http://open.blogs.nytimes.com/2011/01/11/emphasis-update-and-source/" rel="nofollow ugc">New York Times open-source emphasis script</a> which allows users to highlight and link to specific text within an article or post.
In their own words:
<blockquote>
Emphasis provides dynamic paragraph-specific anchor links and 
 the ability to highlight text in a document, all of which is 
 made available in the URL hash so it can be emailed, bookmarked, or shared.
</blockquote>
The plugin allows for permalinking and highlighting of text on a paragraph and sentence level. No need to set anything up. Just install, tap shift twice, and start highlighting.
See <a href="http://open.blogs.nytimes.com/2011/01/11/emphasis-update-and-source/" rel="nofollow ugc">The New York Times</a> for syntax more information on general usage.
Questions, comments, suggestions? Please leave them on the <a href="http://ben.balter.com/2011/01/11/wordpress-emphasis-plugin/" rel="nofollow ugc">WP Emphasis Plugin page</a>.
Enjoy using WP Emphasis? Feel free to <a href="http://ben.balter.com/donate/" rel="nofollow ugc">make a small donation</a> to support the software’s continued development.

WP Emphasis

One-click implementation of the New York Times open-source emphasis script for highlighting and permalinking text.

Ice Visual Revisions vs WP Emphasis