There are always claims of false positives when Google does something with the algo. A lot of these claims are incorrect, the result of webmasters not looking at their sites harshly enough to see what the algo is seeing. I've never been convinced there were any false positives, until Panda hit people I know, whose sites were extremely unique and creative, nothing like "content farms." But they were, we agreed, perhaps a bit "over-optimized" - targeting hot keyphrases and so on, which we somehow thought might be part of Panda.
But supposedly that's not part of Panda, because now we know it's part of Penguin. Right? Or is that right?
When Panda came out, and we heard is was about thin content, I knew one of my sites was vulnerable. I was working slowly to improve the content, but my focus was on other sites so I was just waiting for Panda to catch up and hurt me. I had never been any good at link building, so all my links on all my sites are natural. On this particular site, my backlink profile was really weak because in that niche, people are very stingy about giving out free, natural links. I thought that might get it in trouble with Panda, too.
To my shock, Panda left my site alone, but Penguin got me - on my least optimized site. Yes, I realize I'm self-reporting and you have the right to be skeptical.
One possibility: my Penguined site is over 6 years old, so I have the sort of unsolicited spam links everyone accumulates over time, like updowner. I only have a handful of quality links, because of my lack of skills at link building of the white or black hat variety. Could Penguin be mistaking weak profiles on older sites for spammy profiles?
Or are Penguin and Panda intersecting and overlapping in ways we still don't understand? Why did people with unique and interesting content get Panda slapped, and why did my least optimized site get Penguin?
[edited by: tedster at 9:35 pm (utc) on Jul 3, 2012]