After about a week or so of release candidates, the final version of Firefox 0.9 has been released. So far, I haven't noticed much of a difference; apparently the downloaded file is smaller (about 4MB; I forget what it had been previously) and they've moved the location of the Extensions and Themes menu from Tools->Options to their own seperate entities under the Tools menu.
Oh yeah, and they've changed the default theme to Winstripe, a theme (supposedly) based off of the Mac OS theme Pinstripe. I've known about this for a week, when I came across a post by the developer of the old default Firefox theme Qute, and I haven't seen such an outpouring of negativity towards the Firefox developers that it made me laugh. People are actually refusing to switch to Firefox 0.9 just because they don't like the theme, and will wait until someone ports Qute as a theme for FF 0.9. Lame.
Another group I discovered after reading the 70+ pages of the above thread are the 'How are we EVER going to convert those poor, innocent IE fiends to the highly superior Firefox with this crap as the default theme?' Get over it. If anything, I think the new icons match closer with Win XP than Qute's icons ever did, and even if one uses an older version of Windows or uses XP in classic mode (as I do), the icons still look good. I haven't looked at this version in Linux (YET; hopefully I will have a useful Linux box sometime in the near future), but I'm confident in saying that the icons will look good with that OS as well.
To put it bluntly, Qute is ugly. I always replaced the default theme with another theme I liked better, just because Qute seemed so bland to me. However, I'm in love with Winstripe and I'll probably actually keep it as my default theme. I'm very surprised I like the default layout because that usually isn't the case for me. I don't think people who want to make the switch from IE to FF will be confused because of the new theme, and I think both Qute and Winstripe do a great job at keeping things simple for those new to the browser. I just happen to prefer Winstripe.
Funnily enough, people complained in the same manner about Qute when it first became the new default theme for Phoenix about a year and a half ago. Go figure.