Eirudo

<p>Embed YouTube videos and keept their aspect ratio, just using simple shortcode.</p>
<ul>
<li>Simple shortcode, can be used in the posts or widgets.</li>
<li>Using default YouTube Embed Code (iframe), but make it responsive</li>
<li>Custom aspect ratio, if you want set different porpotion size.</li>
<li>Auto centered position. So if you insert it on your post section, the video always on center-aligned.</li>
<li>Lazy Load supported.</li>
<li>100% Free! And no ads or even trackers inside.</li>
</ul>
<h3>Arbitrary section</h3>
<h3>A brief Markdown Example</h3>
<p>Pros:<br />
1. Simple, only using shortcode to use for individual video each shortcode<br />
2. Lazy Load supported<br />
3. Custom parameters for advanced use</p>
<p>Cons:<br />
1. Only for simple use,not for advanced playlist. Embedding one video for each shortcode.</p>


Simple YouTube Responsive

Perfect

You can add a line to your functions.php to make videos responsive if you're doing your own theme. However, if you're not, this plugin works beautifully and gives other options like lazy load, etc. 

If doing your own theme, add: add_theme_support( 'responsive-embeds' );

Works Beautifully

Embed responsive YouTube videos using simple shortcode. Lazy Load supported.

mhawksey

<p><a href="http://www.rsc-ne-scotland.org.uk/mashe/utitle/" rel="nofollow ugc">uTitle</a> is an experimental tool which uses Twitter to allow users to make free and timeline based comments on YouTube videos. The original concept is <a href="http://www.rsc-ne-scotland.org.uk/mashe/2010/06/convergence-youtube-meets-twitter-in-timeline-commenting-of-youtube-videos-using-twitter-utitle/" rel="nofollow ugc">explained in detail in this blog post</a>, but the basic idea is video are played in custom interface which lets users ‘tweet’ comments. Part of each tweet includes a hashtag linking it to a specific YouTube video and a timestamp from the current point in the video. Tweets are stored in the <a href="http://twapperkeeper.com/" rel="nofollow ugc">TwapperKeepr</a> and temporarily cached on the uTitle site. When a video is replayed in the uTitle interface existing comments appear at the timed points as subtitles and users can also use the timed tweets to jump to part of the video <a href="http://www.youtube.com/watch?v=RVp2F6tDWfw" rel="nofollow ugc">(see this video for a demonstration)</a></p>
<p>This plugin allows you to easily embed commented YouTube videos by enabling a uTitle specific short code (e.g. [utitle mode=1 comment=yes]RVp2F6tDWfw[/utitle]). Options are available to choose the type of player (see Screenshots) and as well as a choice to provide a link to invite users to add their own comments.</p>
<p>uTitle essentially works as the glue combining YouTube and Twitter, subsequently there is no direct control over moderating comments (but it does via TwapperKeepers configuration conform to Twitter’s deletion policy).</p>
<p>This plugin and the uTitle site are not affiliated with YouTube or Twitter.</p>


uTitle Plugin

The uTitle Plugin  allows timeline commenting of YouTube videos using Twitter by integrating with the experimental uTitle tool

Simple YouTube Responsive vs uTitle Plugin