Mozilla's user experience team is doing their nit-pick-y work on Firefox 5 in public — yes, before Firefox 4 is actually shipped. Check out what they're thinking of changing up, including webapp improvements, session restore, menu fixing and other small but nice improvements.
Up top, you can see the subtle shading and tweaking considered for the search bar. It's not a revelation or revolution in Firefox function, but it's interesting to see what the interaction team deems worthy of attention.
For example, Firefox 4's really slick Panorama tab manager might be the place where session restore is activated:
Menus, on the whole, are given a lot of scrutiny: how they react when you mouse over, click, expand and otherwise touch them. What should be inside each menu, too, is being reconsidered:
Previously a function of the Prism project, Firefox 5 will create site-specific webapps. Those webapps might get some very handy inside-link function in their menu bars:
Firefox 5's Add-On Manager looks to get a bit more detailed about the apps you have, where they came from, and what you can do with them (Click image to enlarge).
You can check out more images, notes and ideas from Mozilla's UX team at the full EtherPad post. What do you think of Firefox 5's early-alpha-preview sketches, and what would you like to see looked at in the future?