The Most Commenting Visitors plugin may be able to help with that. It both gamifies your comments and rewards your commenters by displaying the visitors with the most comments in a widget. If the user has a URL, it links out to their URL.
Here’s a look at it in action.
Featured Plugin - WordPress Appointments Plugin
This is an easy-to-use plugin that has a few basic settings in the widget itself. One of the nice aspects of this plugin is that it lets you set the start date for when to start counting the comments. This is good because you can, for example, restart the “contest” every month, putting new visitors on an even playing field with long-time visitors at the beginning of each month.
It also lets you exclude specific users by their email. This is nice because you wouldn’t want the site Admin, for example, to appear in the list. You can also eliminate a user who is trying to game the system by leaving many short but useless comments.
Here’s a look at the widget settings.
This is a simple but effective idea. People love to see their numbers go up. They love it even more when in competition with others. And they love getting links to their site. This simple idea does all of those things … and, oh yeah, it will get you more comments too.
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Photo: Male Comment Icon from BigStock