To get the YouTube thumbnail image, you would either use their API or a simpler method would be to use this format of the url:
Where VIDEO_ID is the last bunch of characters after “v=” in the URL: http://www.youtube.com/watch?v=0TflnHlQMt8
# is the thumbnail number. The choices are 0, 1, 2, 3. 0 is the default full size image (480×360). 2 is the default small image (120×90). 1 and 3 are other optional small images that is not the default thumbnail.
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