Not sure if I can talk about this here so feel free to move or delete it. For the past 6 months or so Circo and I have been going through all the snap videos he made for mame and we are almost done with a complete updated mame set. You should check it out if you run a front-end that supports MP4.
Circo does all the video editing I just help to find missing or videos that have to be redone for quality or just different graphics then the parent rom.
actually doing this has helped me find some bugs in mame which I report to mametesters.