Posted as per the instructions in the Codex.
Media: Twitter Embeds
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 …
embeds
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.