tedster - 2:55 pm on Dec 16, 2011 (gmt 0)
If you have the historical records from whatever analytics program you use, look first for those pages that lost the most Google search traffic when Panda first had its impact on your site.
From what I've seen it is most likely these pages that got the low Panda scores. Then that low score spread as a ranking factor from these "seed pages" to some degree throughout the other URLs of your site. Ideally, you would improve these seed pages pages - take them beyond whatever "shallowness" you can clearly see. When that seems impractical, then remove them. Or if that also seems impractical, then noindex them.