I appreciate this is probably too late in the development cycle but I have a key issue with most catalog software.
I use PM as the front and back end to my workflow (news/stock) for sdelection, metadata and uploading. It is wrapped round C1Pro as my raw converter/ editor and sort of my catalog; it would be good if PM and C1Pro integrated more closely but hey, I can live with it. However I would prefer to use proper catalog software to manage my archive. Unfortunately none of them (except the combined raw converter/catalog tools) use the post-production version of an image for the thumbnails or even the large preview. It would be good if Catalog could, it would be major benefit for us LR or C1 users.