If you've ran across the issue like I have, chances are YouTube videos do not fit your website perfectly. My website and it's columns are not the same width as a YouTube video, so if I post a video either in my main column, or side column, it is either going to blow out the column (right side), or not fill up the column (main column).

Lullabot has just released a great video training on Drupal. More information below, including teaser video.