Post Format: Video (WordPress.tv)
Posted as per the instructions in the Codex.
Tag: video
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.
Edge Case: Many Tags
This post has many tags.