The "subSilver2" style is likely to be dropped at some point in the future, though we are still in discussion as to what to do with it.
Thanks. That makes me nervous because browser support for CSS still seems touchy. I've tried to change a few things in prosilver. It looks good in FF, but destroyed IE 7. It's too tedious fiddling with the nuances of styles and how all the browsers handle it.
Maybe a better alternative than reverting to subsilver2 would be for me to replace more sensitive (complex) areas of prosilver with table layout (more predictable control). Like the forum and topic list. Apply Prosilver's style to that.
I know prosilver's markup and style is preferable to using tables for layout. But, it's really treacherous to change some of the more complicated parts.