Yes, you’ve probably already seen it: I’ve written a 3-page article discussing the Panda update’s impact on Squidoo and Hubpages traffic, and what lessons we can learn from it to stay ahead of the Google wrecking ball.
You may notice that the root message boils down to, “write unique content that your readers find USEFUL,” which isn’t exactly earth-shattering, but it’s amazing how many people try every approach but that one.
Unfortunately, if you publish on an open article-submission site like Squidoo or Hubpages, your content is partly judged by association, so you can get marked down by Google even if that’s exactly what you’re doing. Fight back by encouraging quality content on your favorite sites and leading by example.
I think Hubpages is taking some good steps to put its house back in order (as is Squidoo). We’ll see if Google agrees a few months from now.