Planet13 - 7:43 am on Mar 9, 2012 (gmt 0)

Your most relevant category pages will takeover positions of products, but this won't change your traffic in any way.

Hmm... I am interested in why you say this. Could you elaborate further?

I am thinking if a category page were to rank, say, 5th in the serps for the term Iron Widgets, maybe noindexing the various Iron Widgets Product-Level pages would help the Iron Widgets category page rank higher for Iron Widgets?

As for Panda, I am less concerned. I haven't been hit by panda, although since I described my site as having "overlapping" content, it may appear that I was worried about it.

But there must be tons of ecommerce sites where the product pages are nearly identical except for one attribute (say, a 10 inch widget instead of a 12 inch, 14 inch, 16 inch, etc.,)

And while they may not be susceptible to Panda, maybe they are somehow getting caught up in the rest of the algorithm?