> Over the last week ... the Like button appeared on 8.4M websites covering 2.6B webpages, the Share button on 931K websites covering 275M webpages, and there were 2.2M Facebook pixels installed on websites
Yes, but that 8.4M websites is out of a universe of ~375 million websites - so it's a very small percentage (I am using the number of sites that BuiltWith tracks, which probably isn't all websites, but it's a minimum number). The pages number is meaningless, because sites that use it will use it on every page they have - if I have a site with 2 million auto-generated pages, then I account for 2 million of those web pages.