Okay, this is somewhat embarrassing to say

but, I'm close to being a giant squid (50+ lenses), but mostly I set 'em and forget em. Most do not have the option for comments, but if any of them do, I've never approved them.
While I know there are some people who put up Lenses because the lens itself makes them money or just because they have something they want to tell the world, most of us set them up to direct traffic to our own sites.
I do lenses because they give me high
pr backlinks and traffic to my money sites. I don't care about you. (Don't take it personally

)
If you want to get backlinks from lenses, blogs, etc. you've got to look for places where the site's owner wants to build community. If that's not there, the chances are that your comments aren't high on their radar.
Stacy