Aaron Axelsen

Overrides the <code>wp_notify_moderator</code> function located in pluggable.php. By default, wordpress does not notify a comment author of a moderation 
event. This plugin will look at all users in the blog, and notify anyone who can moderate the plugin, along with the admins and the author 
of that post. This has been tested and does work with WPMU as well.

Post Author Comment Notification

Overrides the wp_notify_moderator function located in pluggable.php.  By default, wordpress does not notify a comment author of a moderation

Newt Labs

This simple, lightweight plugin solves one particular issue. WordPress doesn’t include any alt text or a title tag when using Gravatars. This addresses that by using the comment author name for each of your comment’s Gravatars, and for any other Gravatar usage it should use the authors display name.
So if you create a post it will use your name for your Gravatars Alt text and Title tag and then for the comments it will use the commenters name for their Gravatars Alt text and Title tags.
With this plugin you can squash those pesky warnings given by SEO reporting tools that look for missing alt text and title tags.
<h3>Important Notes</h3>

Fix Gravatar Alt Text & Title Tag

Applies comment author name to Gravatar's Alt and Title tags in comments and author display name to Gravatars site-wide.

Post Author Comment Notification vs Fix Gravatar Alt Text & Title Tag