On YouTube, dislikes is a complete failure, really. Never really used, and when it is, it's either abuse, a massive amount of dislikes or just that one dislike any video gets without a reason. Not only that, the dislikes don't seem to count towards the video's performance (reasonably so). It's hard to interpret the dislikes, which is why comments are way more valuable.
RE: Down voting : A Motivational Killer or A Strategic Use of Power?