MacRumors.com

Computerworld notes that the latest Webkit nightly builds offer considerable performance boosts over the current public Safari build (3.0.4) -- with Javascript benchmarks over 2.5x faster in some instances.

While these performace boosts in Webkit date to at least November 2007, Weintraub speculates that the optimizations will find its way into the just-beta'd Safari 3.1.

Indeed, we've managed to track down Sunspider Javascript benchmark results from the same build that Weintraub used (r30090) vs Safari 3.1 (Beta) on a Core 2 Duo 2.2GHz. The results:

Shorter times are faster.

Webkit Build r30090: 3495.8ms
Safari 3.1 Beta: 3408.0ms
Safari 3.0.4: 9302.3ms (extrapolated)

Amongst other improvements, the latest Safari beta does seem to incorporate the speed optimizations found in the latest Webkit builds. Webkit is an open source project that serves as the basis for Apple's Safari browser. Webkit's nightly builds offer end-users access to the latest (potentially unstable) Webkit updates. A number of other browsers also use Webkit and will also benefit from these improvements.