Small amounts of "Panda flux" have tended to follow after each iteration. And that flux has meant some sites that were hurt regain traffic (some or all) - and likewise some sites that got a boost have lost some or all of their gains.
This flux tends to affect only a small portion of all the sites impacted, whether positively or negatively, and so this "Panda flux" had seen little comment here in the past, just a few posts.
As a matter of fact (and human nature) we see many fewer posts from websites that gained in any Panda iteration than we do from those whose traffic suffers. That does tend to give a skewed sense of what's going on. So those who have access to large amounts of rankings data - not just their own niche - have an advantage in seeing the bigger picture.
I wish I had more of that kind of data myself. I only have a taste, and so far it hasn't been enough to indicate any conclusions, but it can be tantalizing.