I was about to post something about it I downloaded it at work and it was great. Not really different from the nightly builds I've been using, but I love the new icon (will take time to get used to the name). The new download manager is nice -- I like it a lot better than some of the other "download managers" they've run out for the Mozillas before. The browser just seems to have a cleaner look and feel to it. I can't really put my finger on it, but it just "feels" better . . . If you haven't tried it yet, <a href="http://www.mozilla.org/products/firefox/">Give it a whirl</a>. You'll be glad you did!
I downloaded it early this morning... Like Vengeance said it's not very different from the nightly build they have released. Not a huge improvement but definitly worth upgrade. (it's free why not)