Yeah Tacimala, they have already taken that functionality away. They are now talking about removing the Supplemental tag away completely. The reasoning according to Matt is that the supplemental index is being updated more often so it is more like the regular index. He also intimated that it would force
SEO's to focus on traditional
SEO techniques and not try to get their supplemental pages in the regular index since there is no supplemental index anymore.
I could see this going two ways. The first would be those supplemental pages get pulled into the regular index. The second would be those pages get dropped out of any index. In a way it would be preferable to have the pages be removed because at least you know there is a problem with them, which would help you figure out which pages need work. If they are in the index then you would need to do a bit more work to figure out what needs help. Either way still requires more investigation than the current method where you see exactly what pages are supplemental and need work.