GoogleGuy is still active in the forums, updating Webmasters on Google's latest changes. He explained earlier this morning that we should be expecting "fresher supplemental results" in the index.
Okay, I believe most/all U.S. users should see radically fresher supplemental results now. The earliest page I saw was from Feb 2006, and most of the ones that I looked at averaged in the ~2 month old range. As data gets copied to more places, the fresher supplemental results should eventually be visible everywhere, not just the U.S.
Forum discussion at WebmasterWorld.