littlegiant - 11:00 am on Aug 29, 2011 (gmt 0)
I find that a ranking loss as a result of Panda quality score a very specific thing that is unlike other ranking losses. My experience has been that if a page is affected by a lower Panda quality score, it loses all ranking, and I mean all ranking for many relevant longer tail keywords while it can still rank well for shorter tail keywords.
For example, I've seen time and time again, pages on my site that got hit by Panda rank solidly in the top 5 for 'blue widget' but is nowhere to be found in the top 900 for 'small blue widget' even though the page title tag and h1 tag actually read 'small blue widget'. This is something I've never seen before. Pre-panda, a loss of ranking would typically affect the short tail keywords first while the long tail would weather the storm better. My loss in traffic due to Panda has been primarily as a result of a complete loss of ranking for longer tail keywords and, in fact, has taught me to have a much greater respect for the huge amount of traffic you can get from the long tail.
Penalty or not, this past six months has been like Backwards Day for me in the SERPs. To me, getting hit by Panda is like something that says, You can have some meat but no potatoes! Whereas Pre-panda it would be the opposite, e.g., You can have some potatoes but no meat because your page isn't 'relevant' enough.