For all my protestations, I did switch. There were plugins I wanted to use, that just weren't available for Mozilla. I'm still not quite used to looking under "Tools" for my program preferences (a very Microsoftian shift, I must say), and I can't get the tabbed browsing behavior to match the cleaner and more intuitive tabbed browsing experience in Mozilla. And I miss the memory-resident feature that lets Mozilla pop up near-instantaneously whenever I click the dinosaur-head.
But I did switch, and I have been using Firefox consistently throughout the last few weeks. I only switched to Mozilla when I needed to troubleshoot problems for others, or set it up on other people's PCs. At the end of this time, I still advocate Mozilla over Firefox for casual users: It remains more solid, more bug-free, and more polished at the presentation and installer level. It's what I set Mom & Dad up with on their PCs.
My opinion of Firefox hasn't really changed. I still think it's the kewl kidz browser, and it looks and feels like it -- which is to say, stuff often doesn't work right, or plain doesn't work -- it crashes frequently and churns at unexpected times -- and many things still show distinct signs of the developer's ego-centric contempt for objective evaluations of usability. But it's still the train that's going forward; if that's where I want to go, that's the train I get on.
LATER: Most Firefox plugins are now invalid! Mirabile dictu! And more remarkably yet, there's no way to tell (at release plus several days as I write this) which extensions are compatible with 1.0. So the process of trying to produce a browser for mass-public-consumption has taught the Firefox team exactly nothing! Why am I not surprised....
On the plus side, some things (like the Extensions dialog) are no longer cruelly slow. And the installer seems to work rather well under Linux.