I've been using Firefox 3 for the past few weeks, and today it's officially released. I've found most of the new features to be unobtrusive and generally useful, so I'd recommend it to anyone. The folks at Spread Firefox are calling today "Download Day", and are attempting to set a Guiness World Record for the most software downloaded in 24 hours. You've got till 5:00pm UTC (2:00 am tomorrow morning our time), so get downloading!