I've been using the FFox 3 Release Candidate for some time now - it has a ton of improvements over 2.0 in terms of both features and performance, but it may take a little while to catch up w/add-ons (probably a week or so).
That said I can't download the stable version because
* Their site is flooded with requests at the moment, as they are trying to break the Guiness World Record for downloads in a day (no joke)
* In the rare event that their site is responding, it still has an old link for FFox2.0.
If anyone can provide a link for the 3.0 download it would be appreciated.