This website uses a privacy-enhancing Pelican plugin
This plugin, the “YouTube Privacy Enhancer,” is a conceptual replication of the Electronic Frontier Foundation’s MyTube plugin, which pre-caches thumbnails of embedded YouTube videos so that users are not tracked by Google until they explicitly “opt-in” by clicking on the thumbnail (at which point the thumbnail is replaced by the video embed iframe). I do this to keep external tracking cookies from your computer as much as possible; I think that this is an ethical practice. A full explanation of the plugin’s rationale and inspiration (the EFF’s MyTube plugin for Drupal) can be found here.
Here’s an example: by writing
the video from http://youtu.be/QHmML7bu-iM is embedded like this (click to view):