[nadocrew]

It's to fix youtube's weird thumbnail choosing algorithm

[xxbondsxx]

You can manually choose the thumbnail:

http://support.google.com/youtube/bin/answer.py?hl=en&an...

The days of gaming youtube thumbnails by putting in frames at the 50% mark are long gone..

[flinner]

Nice option, but not perfect. It still only gives you three thumbnails to choose from.