I have seen last days some big changes in site counts when you make a search, I know there changes everyday, like you make a seach for a keyword which gives you 4mill results it can have a site count from between 3-5 mill sites thats normal, but today I saw on a normal seach where the site count is 4mill., this time there where 12mill sites as results, thats a huge difference.
zeus
p.s I dont think it is a update, but it can be a beginning of something.