Here are some results of benchmarking on my home computer. It shows that Chrome is still much faster than IE9 on all major JavaScript benchmarks. The IE 32bit version is a little better, but Win7 64bit is outselling Win7 32bit by a 3:1 margin, so this is what many users will experience.
My system is a Intel Core 2 Duo E6550 @2.33GHz with 4GB of RAM running Win7 Build 7600. The version of IE tested was 9.0.8080.16413 64bit and the version of Chrome was 10.0.648.204.