What I found was that any page that had more than 80% similar content and over 150 words received no traffic.
Thanks for sharing those numbers - sharp analysis. The idea that Panda needs a certain minimum amount of content to rate a page is definitely something to chew on.
A vocabulary note. Google uses the phrase "thin content" to refer to affiliate content that is basically just reprinted from the parent company's feed with little or no added value. So thin content can still be a lot of words on the page.
They use phrase "shallow content" to refer to content of any length that just doesn't say much that is of real value to the reader. Shallow content is bread and butter of content farms - and all manner of MFA websites.
I'd say what you've identified is simply "short content" and there are all kinds of legitimate reasons for some URLs to have short content. Serving short informational notes in a pop-up window is one obvious example. Sometime a point-of-sale page just doesn't need any "padding" either, so don't risk turning a page into shallow content by adding fluff copy.
[edited by: tedster at 1:47 am (utc) on Sep 21, 2012]