Really cool to read through and find so much awesomeness added to WordPress 3.6 while I was gone. I should take three weeks off more often. — Andrew Nacin (@nacin) April 3, 2013 This post tests WordPress‘ Twitter Embeds feature.
Post Format: Video (WordPress.tv)
Posted as per the instructions in the Codex.
Post Format: Video (VideoPress)
[wpvideo tFnqC9XQ w=680] VideoPress, especially as a video post format, usually provides some unique styling issues. You will need to install Jetpack or Slim Jetpack plugin to turn the shortcode into a viewable video.