Windows 32bit Family XP RTM - 5.1.2600
XP SP1a - 1106
XP SP2 - 2180
Server 2003 RTM - 5.2.3790
Server 2003 SP1 - 1830
Server 2003 SP2 - 3959
Vista RTM - 6000.16386
Server 2008 Beta 3 - 6001.16510
Windows 64bit Family XP 64bit RTM - 5.2.3790.1830
XP 64bit SP2 - 3959
Server 2003 64bit RTM - 5.2.3790.1830
Server 2003 64bit SP2 - 3959
Vista 64bit RTM - 6000.16386
Server 2008 64bit Beta 3 - 6001.16510
Tuxradar did some benchmarks comparing Firefox's Windows and Linux JavaScript performance. 'We did some simple JavaScript benchmarks of Firefox 3.0 using Windows and Linux to see how it performed across the platforms — and the results are pretty bleak for Linux.' Later on, they tried Wine. 'The end result: Firefox from Mozilla or from Fedora has almost nil speed difference, and Firefox running on Wine is faster than native Firefox.'