Ars has some benchmarks showing Firefox 3 may beat even Opera in performance:|
Mozilla developer Stuart Parmenter has written an overview of the tactics that were used to reduce Firefox's memory footprint and also reveals the results of a memory benchmark he performed to compare Firefox 3 with other browsers. The memory benchmark, which uses the Talos framework and was conducted on Windows Vista, replicates real-world usage patterns by automatically cycling pages through browser windows and then closing them. Firefox 3 used less memory than Firefox 2, Internet Explorer, and Opera, and it also freed more memory than the other browsers when pages were closed. Safari 3 and Internet Explorer 8 could not be benchmarked because they crashed during the test. I hope this turns out to be true of the final release. I love FF but the memory leaks make it hard to use without the occasional restart.