travelin_cat - 8:36 pm on May 25, 2012 (gmt 0)
I have never really found a reason to have comments. The people that like the video can give it a thumbs up or down, so I don't really see the need to have anyone add anything else.
With a very active channel, you could have hundreds of people commenting and you would have to respond to many of them. Not my idea of a good way to spend my time.
There may be a boost to ranking with lots of comments, as they can be seen as a citation, but nobody really knows for sure how much weight they pull, except Google.