This is worth quoting at length:

On November 9th, 2004, you all started a movement. Spread Firefox, supported by tens of thousands of contributors, took just 99 days to deliver 25 million downloads of Firefox to a world of people desperate for a better Web -- a Web that didn't overwhelm them with pop-ups, a Web that didn't infect their systems with viruses and spyware, a Web that was fun again, simply put, a Web that worked.

In less than six months, you all doubled that number to 50 million downloads, turned open source into a household word and reasserted the supremacy of choice and simplicity.

It took the Spread Firefox global community of activists only one year to reach the 100 million downloads mark and to let the world know that innovation was alive again on the Web.

And just one year ago you all helped to double that number again, to 200 million downloads. More than 50,000 of you, with Spread Firefox buttons and banners, not only helped Firefox achieve an amazing download milestone, but you all helped to make Firefox one of the world's most recognized and respected brands.

Today, you all have done it once again. With your amazing efforts, Firefox has reached 400 million downloads and demonstrated that not even the world's most powerful companies can keep people from a better, safer, and faster Web experience. You all, the grass roots and the heart of the Firefox movement, have helped hundreds of millions of people find that better, safer, and faster Web.