Every single time a new Firefox version is about to come out, someone jumps the gun and writes a blog post like this, linking directly to a single Mozilla FTP server. Usually, they're actually linking to a release candidate anyway, but as a matter of practice, you should use the links that Mozilla provides on the Firefox download page in order to take advantage of their system of mirrors (e.g., http://www.mozilla.com/products/download.html?product=firefo...).