Yeah, similarly, the 'Firebug' toolbar for Firefox is an awesome Javascript debugging tool that I really can't do without.
That said, at work we do huge business in the orient (especially Japan), and I have heard before that Opera is the most popular browser there. Dunno how true that is, I'm just fucking delighted that our "IE6 is the main platform, everything else doesn't matter so much" policy has finally been reversed after months of long e-mails from me
If Opera can be devved up to the nines, I'd be definitely interested.