Not sure if this is an update, rollback or whatever but I thnk something has happened. I lost a whole load of pages on the previous update (around 23 october) but most of them seem to be back on the "pure search" today (yippee!). Looks like an update rather than a rollback, because at least one page which wasn't in the pre-oct-23rd index (but was in the post-oct-23rd index) is showing. :)