Proportional whole-page zooming came in FF3. I don't know if it can track this on a per-site basis though. That would be a very nice addition to Safari though.

My FF4 changes-
* re-arrange button bar (customize) Back/Forward - new tab - home - refresh/stop - address - (delete google search) - various add-on buttons
* FF3 look-alike theme (return to good looking buttons, basically)
* tabs on bottom (tabs adjacent to pages)

Can't think of what else I did just now, but after doing that much things were pretty much back to normal for me.
It wasn't hard to do these quick customizations and shouldn't stop anyone from enjoying FF4 vs. FF3.

The one thing that I absolutely must do on every FF4 install is to install Status 4 Evar to bring back the status bar. The goofy pseudo pop-up status display is ugly and annoying. No idea why they changed this.

Because Chrome did it. And both browsers annoy me with that at work, where the status bar likes to pop up over UI elements in a few of our web based dashboards.

The Chrome way seems to be the motivation behind a lot of recent Firefox changes lately, including the amazing growing version number. Chrome is up to 11 now, with 12 expected in a few months. Firefox expects to be at version 7 by the end of the year. Would be nice to see browsers try and differentiate themselves, not all become the same thing from different groups.

The pop-up status bar notice will move to the opposite side of the window if you mouse over it.
That doesn't address the issue of wanting to *see* what's under it without mouse action, but if you have the status bar solidly taking up space you wouldn't be able to see that part of the page anyway.

I'm not that bothered by the missing status bar, but there were some status messages that I liked to see. I'm getting used to not needing to see them.

Yeah, Chrome became a competitive browser by not trying to be Firefox. Firefox will cease to be a competitive browser if it keeps trying (and miserably failing) to be Chrome.

Both FF3 and FF4 do track this setting per-site, for me here at least. Nice.

And the missing status bar at the bottom is a godsend for small screens, like netbooks and android devices. Still, there ought to be a checkbox in View-->Toolbars to toggle it (there isn't).

Cheers

I fear that extension developers will drop support for statusbar icons since it's no longer there by default, and it takes more than a simple toggle to turn it back on. For now, I've only lost one such icon: Greasemonkey's.

I've had to reconfigure AdBlock+ to show it's icon up top rather than in the (missing) status bar.