As I said above - the transition logic for FF2/IE/etc users was not thought through AT ALL.
Given it's a smart bar, I expect it to be more flexible in its configuration, so that I could adjust its smarts as needed. E.g. it could have configurable weights that control how important a match in particular piece of data is. This way I would've zero'ed the importance of everything, but the matches at the head of the URL and happily went about my business without ranting :)
Again, this sort of flexibility is not a hard thing to implement nor does it pollute or burden the UI in any way. Why this or something similar didn't make it into a production release is beyond me.
There are probably a bunch of people like me who have grown quite accustomed to using the Firefox address bar as a quick way to do a Google i'm feeling lucky search. For me, as an FF2 user, this fits quite perfectly with that pattern of usage, and actually extends it conveniently.
Like you I do get tripped up when I try to type a straight URL in there though. Maybe if they raised the awesomeness level a tad they could do some basic pattern matching to recognize when an explicit URL is being typed there. Until then it's just a "cool" bar in my book.
My problem with "awesomebar" is that while it does bring up the sites I visit often (which FF2 did, and given they're a small number of social/news sites; /., reddit, hn, facebook, nytimes, etc its not exactly difficult to list), the order they're listed gets mixed up every time I try to visit a site.
reddit.com showing up ahead of news.ycombinator.com when typing "news" for example doesn't make me like this new way of figuring out what URL to go to (guessing randomly? I'm sure there's an algorithm behind it but after using it since RC1, it still looks random to me) what URL I want when I'm typing the URL in the URL bar.
At first it was a little messy but I've gotten used to it so it's fine by me.
Not really.
It looks like I submit more than I read. So the "awesome" bar puts "submit" before the "index" page. Counter intuitive to what I really want, the index page where if I have to I can add /submit. It just means I now look at line 2 if I want to read.
The awesome bar uses historical data from previous searches, so if your search for "news" always ends with you clicking on HN, it will put that at the top. Over time, the bar will learn your preferences and become much more useful.
I hated the bar at first, to the extent that I considered going back to FF2. For example, I used to always type "en." to find a wikipedia page, but that no longer worked well. Now I love being able to type in parts of pages, and I no longer use bookmarks since I can just search my entire history. The only thing missing is the ability to sync the history and awesome bar training to other machines, which we're working on ( http://labs.mozilla.com/2007/12/introducing-weave/ ).
Disclaimer: I work for Mozilla :)