Chrome is WebKit, WebKit has an amazing inspector/Firebug clone. In using both, I actually prefer the WebKit inspector. I haven't used Chrome yet, so I'm not sure what magical incantation is required to activate the inspector (in Safari it's part of the "Develop" menu"), but it should be there.
I'm not sure what your point is, but Chrome doesn't use WebKit for JS, it uses Google's internally developed V8 engine, so don't expect JS to always run identically in Safari and Chrome.
