Google's blog has announced that their Supplemental Index has now been removed and will no longer be a factor in the search results. This part of the search engine's index was a 'reserve' list of web pages that might have been updated less often, duplicated content or not flagged as relevant content for other reasons, other these pages would appear in very specific searches if the main index couldn't produce enough results.

Supplemental results used to be flagged within the search listings up until several months ago, when Google dropped this indicator. Now their announcement says that advances in their technology enables the full index to be used within all search results, so that the supplemental definition doesn't exist any more.

That's good news because websites should now start to display more indexed pages and there may be more opportunities for a website to appear within 'long tail' search terms. Will this move also mark another step towards the PageRank indicator being removed from the Toolbar as well?