I cannot commit to a web browser. I like Firefox because I think it provides options (via extensions) and the awesome bar is, in fact, awesome. Safari however provides better platform aesthetic and WebKit is a faster rendering engine.
But besides that, I noticed recently that Firefox feels a little “cramped” after using Safari 4 beta. And this is the reason why:
I’m amazed at what 24 pixels can do.
In Safari 4, the tabs are integrated into the title bar, which is why it is smaller.