Ben, I would like what you have described as well & I started on something similar but haven't implemented the versioning script yet.

You use black in the bar to indicate versions.

I use colors in the bar to denote specific versions, i.e. TIFF, JPEG & then if published somewhere.

I have a category called 'Workflow' where I keep this information: It's currently structured w different bar colors to indicate:

1-category assigned
2-keywords assigned
3-converted to TIFF
4-color corrected
5-converted to JPEG
6-on CD or DVD
7-published to web
8-slide show
9-for distribution

As I review this, I think it is too confusing & isn't strictly versioning as 6-7-8-9 denote archival situation. So maybe I should just create a category called Version & include 3-4-5 & another category "Archive" for 6-7-8.

However, in your example, wouldn't you get the same result if you selected one image & used search visually identical images?