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Marcia - 7:38 am on Dec 9, 2005 (gmt 0)
Other than that, I don't think it's so much that the Supplemental Index is taking over, but more like there's a ton of swill flowing into the index, and they're trying to weed it out by setting it into the Supplemental Index, out of the way.
There are some scattered "pages" on quality sites going Supplemental, which could be for several reasons. But one that I think is among the more important reasons is when pages just don't have enough content on them aside from the global elements.