The WebKit SunSpider test regularly changes and these results are from WebKit SunSpider version 0.9.1 running on a Dell Optiplex with a 3.0 GHz Core 2 Duo Intel processor, 4GB RAM, Intel Integrated Video, running Windows 7.
IE9 RC wrapped up the collection of JS tests in just 209 ms, with Chrome 9 the runner up (238 ms) and Opera 11 coming in third with 240 ms.
The 4th position is occupied by Chrome 10.0 Dev (248 ms), followed by Firefox 4.0 Beta 11 (254 ms), Safari 5.0.3 (310 ms), Firefox 3.6.13 (753 ms) and IE8 (3746 ms).
It's incredible how much IE9 has evolved, performance-wise, compared to Internet Explorer 8.
[tags]webkit sunspider,benchmarking,firefox 4,opera 11,ie9 rc,internet explorer 9,ie8,internet explorer 8,c2d,cored 2 duo,dell optiplex[/tags]