Sunspider’s not a very good benchmark; more interesting to me is that they’re nearly even with V8 in V8’s own benchmark.
Though I wonder why they can’t backport TM, or at least a subset, to 3.6; is Firefox so monolithic that improvements to the scripthost can’t be separated from the rest of the browser?
I ran the tests on my Ubuntu 10.10 laptop running Firefox-4.0 Beta8pre and Chrome 9.0.570.0 (64571) and Firefox actually beat Chrome 2943 to 3645 (or a 23% improvement) averaged over two runs.
Err, your last sentence is a bit weird. First of all, 3.6 already has TraceMonkey; what's new in Fx 4 is JägerMonkey, and the integration between it and TM. Second, the Mozilla JS engine is largely developed separately (all of the actual development these days is in a separate repository, which merges semi-regularly with the main mozilla-central repo), but have you seen any other browser backporting anything other than security fixes?
I'm very happy with the result. However, on some javascript intensive webpages, such as https://console.aws.amazon.com/s3/home, it hangs the whole Firefox for a little while. Hopefully with a long timeline to the release, no such issues remained.
http://arewefastyet.com/
Sunspider’s not a very good benchmark; more interesting to me is that they’re nearly even with V8 in V8’s own benchmark.
Though I wonder why they can’t backport TM, or at least a subset, to 3.6; is Firefox so monolithic that improvements to the scripthost can’t be separated from the rest of the browser?