This plugin will install the official Twitter Button provided by Twitter to your Wordpress-Blog.

svil4ok

Twitter Button

Twitter Button is a WordPress plugin that allows you to easily integrate Tweet Button in your blog.

dtsn

TweetMeme Button

The TweetMeme Retweet button is the defacto standard in retweeting - used by some of the biggest websites in the world including Techcrunch.

David Davis

TweetButton

Easily allows your blog post or page to be retweeted. Currently being used by SocialBrite and other members of the social media community.

Pete Mall

WP Tweet

Adds the official Tweet Button from Twitter.

GeekRMX

Twitter @Anywhere Plus

This plugin allows you to easily add Twitter @Anywhere to your blog, enabling the @Anywhere features.

Sudar Muthu

Easy Retweet

Adds a Tweet button to your WordPress posts

makeitrainusa

MaxReTweet – Optimize your Twitter Headlines

Display a list of optimized Twitter headlines for each blog-posts. Increase your Twitter retweets % and inbound traffic.

LinksAlpha

Retweeters

Konstantin Kovshenin

Retweet Anywhere

Retweet Anywhere for WordPress is a nice and easy way to allow your readers to instantly retweet your blog posts through their Twitter accounts.

H. Peter Pfeufer

Twitter has provided a twitter and retweet button. This Plugin adds the official twitter button to your blog articles, pages, archives, categories and rss.
Features
<ul>
<li>Easy install</li>
<li>Panel for easy configuration</li>
<li>Config Button Style</li>
<li>Config Language of Button</li>
<li>Config Your Twitter Account</li>
<li>Config Tweet text</li>
<li>Config display locations (entries, pages, home page, archive, category)</li>
<li>Config position in content (before, after, both, manual choice)</li>
</ul>
Note
If you choose the position as “manual choice” you have to edit your template-file and add the following code at a position of your choice. 
 <?php if(function_exists(‘wp_twitterbutton’)) { wp_twitterbutton(); } ?>
Translations
<ul>
<li>English</li>
<li>German</li>
<li>French (by: <a href="http://www.frankoli.de/blog/" rel="nofollow ugc">Frank</a>)</li>
<li>Dutch (by: <a href="http://wpwebshop.com/" rel="nofollow ugc">Rene</a>)</li>
<li>Czech (by: <a href="http://blog.michalbernat.cz/" rel="nofollow ugc">Michal Bernat</a>)</li>
<li>Hebrew (by: <a href="http://www.sagive.co.il/" rel="nofollow ugc">Sagive</a>)</li>
<li>Hindi (by: <a href="http://outshinesolutions.com/" rel="nofollow ugc">Love Chandel</a>)</li>
</ul>

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