I had some problems with my home Firefox installation (“Home” and “End” occasionally didn’t work in textboxes), so I downloaded the preview release of Firefox 2. So far it’s pretty neat. The icons in the default skin are slightly different and they look great. Tabs now each have their own Close Tab button, which I’m not sure I like. I used to open a bunch of tabs and then move my mouse to universal Close Tab button in the top right corner. After quickly scanning the page I’d close it if there wasn’t anything worth checking out and wouldn’t have to move the mouse at all. Now I have to move the mouse to close each tab, but I guess this will prevent you from closing the wrong tab by accident.
The best feature is definitely inline spell checking for textboxes and textareas. I LOVE IT. It’s not intrusive at all and it just underlines misspelled words with a red line like in Word.