It was a great idea when introduced just a year or two ago but at this point it seems it’s a feature that is no longer supported. Some users report that it only works sometimes. Twitter is famous for having its servers become unavailable so perhaps it’s not ideal to rely on “oEmbed” anyway. Embeds work just fine for YouTube and other sources however.
SOLUTION #1
My team wrote a simple twitter oEmbed plugin that works with a shortcode. So instead of putting in the full tweet URL:
https://twitter.com/helloari/status/423594413600690177
Just put in a shortcode like this:
[twit id=”423594413600690177″]
SOLUTION #2
Another solution is to grab the “full” embed code from twitter. It looks something like this:
<blockquote lang=”en”><p><a href=”https://twitter.com/freshbooks”>@freshbooks</a> <a href=”https://twitter.com/search?q=%23status&src=hash”>#status</a> paypal payments are not working. paypal says it's a known issue with freshbooks today. please give us an update.</p>— ari salomon (@helloari) <a href=”https://twitter.com/helloari/statuses/421349608422264832″>January 9, 2014</a></blockquote><script async src=”//platform.twitter.com/widgets.js” charset=”utf-8″></script>
Remember to put that in the “text” (not “visual”) tab of your post editor.
Here’s where to get the code:
and finally, here’s what it will look like
Embedded tweets in WordPress: It was a great idea when introduced just a year or two ago but at this point it see… http://t.co/cmRTDaPYVb
— ari salomon (@helloari) January 15, 2014
UPDATE: JANUARY 23, 2014
WordPress v3.8.1 seems to fix this issue