I’ve been a Safari user since day 1 given its speed and quality and actually gave up on Firefox on Mac because it was sluggish as hell. But few days ago I’ve installed the latest Beta of FF3 and I must say it is indeed much faster and consume less RAM than any other browser on Mac OS X. Also, the mac-like theme is now pretty neat (don’t forget to use small icons) and substantial improvements have been made all over the place. Firefox3.0b5 has now become my default browser. You should give it a try!