WordPress supports oEmbed, but only in post content. This adds oEmbed support to comments.

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Reviews Plus activates rich reviews for selected content. Turns comments into reviews and provides 100% SERP compatible reviews system.

(14)

Subscribe to Comments allows commenters on an entry to subscribe to e-mail notifications for subsequent comments.

(14)

This plugin allows administrators to globally delete comments (spam, trash, unapproved comments), enable/disable comments on all posts.

(13)

Add a guestbook page which uses the wordpress integrated comments.

(13)

Add a checkbox and custom text to the comment forms so that the user can be informed and give consent to the web's privacy policy.

(13)

Make comments management easier by applying some of the simple hacks the Yoast team uses.

(13)