jwenl

This plugin provides support for using oEmbed in your WordPress blog.
Rick media Example: 
[oembed:http://polldaddy.com/oembed?url=http://answers.polldaddy.com/poll/2431815/&format=xml] 
This will put the selected polldady poll on your blog
Photo example Flickr: 
[oembed:http://www.flickr.com/services/oembed/?url=http://www.flickr.com/photos/23886028@N04/3983995799/in/set-72157622398187791/] 
This will put a Flickr photo into your posting.
Video example Youtube: 
[oembed:http://www.youtube.com/oembed?url=http://www.youtube.com/watch?v=yvdbqcbRH50&format=json]

oEmbedder

This plugin provides support for using oEmbed in your Wordpress blog.

wistia

Wistia’s embed codes are designed to be very durable, but WordPress has a 
history of being particularly troublesome. This plugin adds oEmbed support so 
that pasting a link to the video’s page in Wistia will embed the video. The 
video’s URL must be by itself on its own line for this to work.
As of version 0.6 of this plugin, it is recommended that you check 
“Use oEmbed?” under Advanced Options when generating your embed code.
As of version 0.8 of this plugin, the legacy “Anti-Mangler” feature is an 
option that is turned off by default.
See the Wistia documentation for more: 
http://wistia.com/doc/wordpress#using_the_oembed_embed_code
<h3>Automatic Installation</h3>
<ol>
<li>In Admin Dashboard, go to Plugins > Add New.</li>
<li>Search for “Wistia WordPress Plugin”.</li>
<li>Find the plugin and click “Install”.</li>
</ol>
<h3>Manual Installation</h3>
<ol>
<li>Make a ‘wistia-wordpress-oembed-plugin’ directory in ‘/wp-content/plugins/’.</li>
<li>Upload all files in the repository to the 
‘/wp-content/plugins/wistia-wordpress-oembed-plugin/’ directory.</li>
<li>Activate the plugin through the ‘Plugins’ menu in WordPress.</li>
</ol>

Wistia WordPress Plugin

Enables all Wistia embed types to be used in your WordPress blog.

oEmbedder vs Wistia WordPress Plugin