It's certainly not there yet, but the Web Inspector in recent nightlies is a lot closer to Firebug than the one in Safari 3.1. That, and the advances the WebKit

It's certainly not there yet, but the Web Inspector in recent nightlies is a lot closer to Firebug than the one in Safari 3.1. That, and the advances the WebKit team are making elsewhere, gives me a lot of confidence that it's only a matter of time before Safari has a built-in web development tool and JavaScript debugger that matches or improves on Firebug in every area.