To the applicants here.
I'm using YouTube stats as a metric whether or not our application was read.
We have 5 videos in the application:
1 team video that was watched by someone from YC;
3 videos about teams' past work - only one was watched from California in the last 10 days, and we can't be sure it's someone from YC because it's a public video;
1 video showing the proof of concept of our product - not watched.
So, I'm guessing this is a bad sign for our application? :)
I'm not part of YC so take this with a grain of salt, but I don't think that not viewing videos is necessarily a bad sign based on comments I've seen from the YC founders about the subject. Videos are mainly viewed to see the chemistry between founders. Someone posted on HN the other day who said that last batch their video had 2 views and they got an interview. As long as your written application has all the relevant info, I wouldn't worry about this stuff.
As far as I know, the applications are scored as they are seen, the scores are averaged, and the top n% are invited. So you shouldn't read into the number of views you get.