Well can not say you would really need command line access to see backend server if it really works. I have it working on my server as what is in the program now came from the hack you are referencing. We added the ability to do it but your server needs to have a functioning ffmpeg for it to work.
Here is an example avi it does work
2011-05-25-Video4 - ReefTalk Gallery
Notice the first thumbnail on the preview strip is the first frame of the video so that is a thumbnail made from the video using ffmpeg