Edit: Unfortunately, the images originally included in this post are gone, because of hosting problems in late 2009. My apologies.
I don’t usually like Firefox — it’s bloated, it’s slow and it’s a bit overblown — but I find my Crux builds to be satisfactory. Version 3 is an improvement from my perspective.
It does have a faster feel about it. And the versions I build with optimization flags run even faster, even if they don’t always behave … properly. I get some occasional strange behavior (like not being able to install an extension, or not being able to post a reply to a forum thread) so I have to back off the flags again, and see if that helps at all.
It does seem to be a little more Linux-friendly too. I don’t have to manhandle the font settings any longer, or adopt an out-of-date theme to keep it from looking like a glossy, bulbous tumor on my otherwise smooth and angular desktop.
I have a little more experimentation to do, but otherwise I’m satisfied to use it. It’s not my favorite program, but it will do in a pinch. And with this two-pane style I have (learned from the Gnome Ubuntu desktop, which seems to like to pane the windows by default) it’s somewhat useful.