A bit off the primary topic of but you mentioned a system where people could type a couple of words in review of the site. Was there something about launchly that made you feel like you had to write a lengthy review? Feedback can be any length so you could write something as simple as "Your logo is crappy and I don't see any market for your service." I mean more in-depth is obviously more helpful but there's no minimum amount of helpfulness :-)
Can you think of what would have motivated you to provide feedback (of the non-dissertation variety of course)?
As for the second problem, I guess (personally) I see a huge textbox where you ask for my name, email and an optional website, and I just don't feel motivated. I think you could have a small, anonymous comment spot that felt more like a tweet rather than a post.
Oh and as an aside, I didn't realize that you had the comment overlay button when I viewed a site. Maybe add some words to the icon to make it OBVIOUS for unobservant people like me?
The comment system currently uses Disqus because many people already have an account with them so they don't need another one on launchly. That form you mentioned is their version of an anonymous comment but maybe it is too invasive with the name/email/website stuff? I've been considering ditching Disqus but they bring a lot to the table... I will make the comment overlay button more obvious, thanks.
You could just put a small textarea up in your top launchly info frame where people can leave small page specific comments about sites.
Speaking from personal experience, I went to your site clicked around, looked at a couple of the sites. I did find a few things that I could suggest about them, but didn't have the motivation to write a dissertation about the problems.
Hope this helps.