Final release of Firefox 2.0 is due on Oct. 24, 2006. However Mozilla had pack up everything and uploaded to their FTP server and ready to announce it tomorrow. If you don't want to download with many folks when they announce tomorrow, you can download it today here (link disabled because of this) today!
Some of your favorite extensions may not work with Firefox 2.0 until those extensions are updated. Until then here is how to make those extensions work. Have fun.