About 5 hours after the official release, Firefox 3 has crossed the 2 million downloads milestone on its way to set a really high Guinness World Record.

You can help. If you intend to get Firefox 3, get it by 17:00 UTC on June 18, 2008. That’s 10:00 a.m. in Mountain View, 1:00 p.m. in Toronto, 2:00 p.m. in Rio de Janeiro, 7:00 p.m. in Paris, Madrid, Berlin, Rome and Warsaw, 9:00 p.m. in Moscow, and June 19, 2008 at 1:00 a.m. in Beijing and 2:00 a.m. in Tokyo.

Also, make sure to claim a certificate for your contribution to making history. Go to Spread Firefox to get your personal piece.