I assume you are just talking about web browsers in general, cos the only way to get IE8 to run on Linux, is in a Virtual Box (which does produce a few giggles and amusing for a few seconds).
The latest version of Chrome 5 outperforms any other browser on the planet. Read more about the Dalvik JIT compiler and V8 engine.
I don't care much for synthetic benchmarks, i prefer to judge my browsers on real-life performance.