I’ve been testing Firefox3 for a few days now and it has been a great improvement over previous versions.
The new Location bar – really is the Awesome bar! I’m already getting used to the new look of the suggestions, and sourcing from bookmarks as well as history is a great improvement.
Firefox is finally using sqlite for bookmarks and history. This makes a noticable difference in speed and also allows for some more advanced features in the bookmarks system.
The unobtrusive Password Manager drop-down is another great improvement. It waits until after you submit the form before asking, and it no longer blocks the interface so the user can easily ignore it.
Addons
As for Addons, these have already been updated to support Firefox3:
Adblock Plus
Add Bookmark Here2
ColorfulTabs
Greasemonkey
Locationbar2
Menu Editor
NoScript
QuickProxy
Web Developer
Addons still waiting for updates:
AutoCopy and Copy Plain Text (inter-related)
No-Referer
Organize Status Bar
Paste and Go 2
Permit Cookies
Preferences
I found that a few preference changes are required to optimise the performance and experience:
browser.tabs.tabMinWidth;60 browser.tabs.closeButtons;0 // only 1 close button, on current window browser.tabs.loadDivertedInBackground;true // load tabs in background browser.fixup.alternate.enabled;false // disable automatically adding of www. and .com to urls