Brian Onorio, O3

This plugin makes syndicating your content to social networks easy. While other plugins have 100s of available networks you can connect to, this plugin makes it easy to post share buttons for the 4 big networks: Facebook, Twitter, Google+, and LinkedIn. Who uses Ying Yang and Bamalamadingdong anyway? Once activated, you will see a series of social plugins at the bottom of each post allowing your site visitors to quickly and easily post the content on your site to their profiles on these networks.
The plugin has a robust options panel allowing you to pick and choose which networks to support. You can also customize the Facebook and Twitter plugins in the exact same was as you would be able to if you were pulling the plugin code directly from the supporting website.
Default Options include:
<ul>
<li>Choice of any or all of the following networks: Twitter, Facebook, Google+, and LinkedIn</li>
<li>Customization of tweet content allowing you to use to use the page title or to customize it</li>
<li>Add a Twitter user to the tweets</li>
<li>Add a hashtag to tweets</li>
<li>Include or exclude the Facebook Send button</li>
<li>Choice between Facebook verb to use (Like or Recommend)</li>
<li>Option to include default styles or leaving the styling up to you</li>
<li>Place the Social Plugins above the Post Content, below the Post Content, above and below the Post Content, or place them manually</li>
<li>Restrict the Social Plugins to just the posts, pages, or any other registered custom post type</li>
</ul>
For more information on this plugin and support for this plugin, visit <a href="http://www.weareo3.com/plugins/o3-social-share/" rel="nofollow ugc">O3 Social Share on O3</a>.
Note: The Facebook “Send” button, when activated, sometimes disappears on some browsers after a momentary display. This seems to be connected to a Facebook bug documented here: <a href="https://developers.facebook.com/bugs/299191993489218?browse=search_4f9eab716e1110276007093" rel="nofollow ugc">Facebook</a>.
<h3>Usage</h3>
Simply activate the plugin and you’re all set.

O3 Social Share

This plugin will add social share icons for the 4 major networks to the bottom of WordPress posts.

Nimrod Flores

GooglePlus Multi-Authorship provides a straightforward solution to properly add Google+ Authorship markup to the head of each post and page on a multi-authored site.
It follows the recommended use of the rel=”author” link tag to point to a Google+ profile as described in <a href="http://googlewebmastercentral.blogspot.com/2013/08/relauthor-frequently-asked-advanced.html" rel="nofollow ugc">this FAQ</a> on Google’s official webmaster blog.
<ul>
<li>It adds only the rel=”publisher” link tag on the home page, front page and archive pages</li>
<li>It adds both the rel=”author” and rel=”publisher” on single posts and pages.</li>
<li>The appropriate author’s Google+ profile is used for each single post and page.</li>
<li>You can set a default Google+ profile to be used as a fallback if there’s no Google+ profile specified for an author in his WP user profile settings.</li>
</ul>
For questions and support, please post them at the <a href="http://nimrodflores.com/googleplus-multi-authorship" rel="nofollow ugc">plugin page</a>. I can’t provide quick help if you post your questions in the forum as I am not always in the forums.

GooglePlus Multi-Authorship

GPMA provides a straightforward solution to properly add Google+ Authorship markup to the head of each post and page on a multi-authored site.

O3 Social Share vs GooglePlus Multi-Authorship