Firefox 3 beta 5 is here

Acid3 - 69/100
Javascript has become significantly faster.
In addition, we have a slightly modified interface (for WindowsXP)

As always, the beta can be downloaded at http://www.mozilla.com/firefox/all-beta.html

[UPD:]
Some (many) extensions have been disabled due to compatibility checking. This does not mean that they are not operational. :)
')
To disable verification, go to the address about: config and add a logical parameter extensions.checkCompatibility with the value false

[UPD:]
http://ftp.mozilla.org/pub/mozilla.org/firefox/nightly/ - nightly builds

Firefox 3b5 Portable by PortableApps