Have you participated the Spread Forefox's download day on 17 June 2008? I can't find any exactly number of the downloading counts but it definitely exceeds 8 million times in 24 hours. Mozilla even provides a certification-geneator webpage for all firefox users, no matter you have downloaded it or just wanna a "piece of paper". So, here is my "certification":
However, there is a bad news cutting in after the downloading day. Mozilla has confirmed that there is a known bug existed inside Firefox3.0. Worst, this known bug was actually inspected in version 2.x....Mozilla promises they will fix it and release an upgraded version ASAP. Reflecting back the downloaded counting numbers, I wish they can fix it very soon....