The 5th beta of Firefox version 3 is now available for download. It supports more than 750 changes since beta 4.
Some of the noteworthy alterations include speed increases in the way Firefox handles JavaScript, new Firefox theme for Mac makes it appear as a native app, I really wish they had done this on Vista.
According to the release notes, many of theses improvements were based on user feedback.
After some preliminary testing it does appear to be faster than beta 4.
Download @ Mozilla