WP Welcome Message is the new WordPress plugin that allows you to create message using visual or HTML editor then display them automatically in a fade out or slide up view.
WP Status Notifier lets you send automatic email notifications to given email addresses for the blog posts pending for review. The plugin can also be used optionally to notify contributors when their post is accepted or rejected, The plugin is very useful for moderation in multi-contributors WordPress blogs.
New BuddyPress plugin allows you to manage notification system for all of your BuddyPress site members. Admins can manage all notifications settings including notification settings added by other plugins. After activation settings are applied to new members indivisibly. You can also disable access to notifications page for all members if you like.