[RussianCow]

It helps, but the key feature of Firebug for me in this regard is that, if the object is an HTML element, I can click on it and it will take me to that element in the HTML view. The built-in tools don't have this yet.

[canuckistani]

There is the bug for nearly that exact thing:

https://bugzilla.mozilla.org/show_bug.cgi?id=890402

I linked to this comment in that bug, thanks for the feedback!