Firefox version 3, currently in beta, is impressively faster and less memory-hungry than previous versions. That makes my computer pretty happy. The other most noticeable change, though, has garnered mixed reactions from users of the beta. The address bar has been changed, with much fanfare, into the "Awesomebar".
The new bar is bigger – each site displayed when it drops down gets two lines of explanation that include the URL, the page title, and the searched keywords. But also the workflow is different.
I'm accustomed to typing "wir" in the address bar and seeing it bring up URLs that start with that string, wired.com being the first. The Awesomebar searches all through the URL and page title, and not just in my history but also in my bookmarks, so "wir" brings up fanpages for Wire and The Wire, as well as miscellany like a site whose page title includes "cell phones, wireless phones, sim cards".
The bar learns adaptively, they say, and is supposed to give more weight to sites wherein your string appears at the beginning of the URL rather than somewhere in the middle of the title. But it breaks a major commandment of interface design: don't radically change the behavior of something everyone's used to, especially without including an option to return to the expected behavior.
Users are unhappy. There's an extension called oldbar that makes the bar look like the old one, but its annoying behavior is still the same. Rumor has it the option is so deep in the new code that it's hard to toggle, but come on, people.
(image borrowed from Mozillazine commenter Fedorov)
See Also: