Guahan Web

This plugin gives you the flexibility to add Ajax handling for your comments to keep the page from having to refresh every post. The administration panel will allow you to customize your processing, success and error messages.
Additionally, this plugin gives you the option of setting up the WYSIWYG editor for comment submission as well. The admin panel will give you the option to show/hide various button groups for the editor and only allows basic editing capabilities. If logged in as administrator, you will still receive the full WYSIWYG editor for your commenting.

GuahanWeb AJAX & WYSIWYG Comments

Adds customization for Ajax commenting and allows for enabling of custom WYSIWYG editor.

Christiaan Conover

Author Customization gives you much more flexibility in managing post and page author data. Your author data will no longer be tied solely to the WordPress user system, and can now be managed on a per-post basis. Author name and description are saved with each post, allowing you to preserve this information as it was when the post was published.
Features
<ul>
<li>Per-post author display name and biographical info</li>
<li>TinyMCE (WYSIWYG) editor for user profile and per-post biographical info</li>
<li>rel=”nofollow” link inside biographical info entries</li>
</ul>

Author Customization

Author Customization expands core author management with features such as per-post author information and rich user bio editing.

GuahanWeb AJAX & WYSIWYG Comments vs Author Customization