@mitch074 I don't agree with you in several points. You're right about the few loose of firefox, but take in mind that Opera is weak in HTML5 (yet not fully completed), HTML5 Hw Acceleration (the same), WebGL (is dependent of HTML5), and Memory Managment; the last one is not a loose because that helps to maintain the closed tabs (for open closed tabs quickly). But Firefox is weak in CSS, and that is not acceptable, i'm sorry, so you are not helping firefox .
The stuff you say about complementing firefox, applies for Opera too, but in Opera that stuff has the names of Extensions and Widgets, and Opera barely needs that because all the good features are already in Opera. Maybe the part of the debugger console is true, i'm not a website developer, but Opera have Dragonfly IDE, I think is the same, but i'm not sure, maybe i'm wrong here.
I'm a windows user, so Opera is great for Windows users, if you use Linux, Mac and Windows, maybe firefox in there is better (because of his multiplataform form, not because works betters than other browsers in talking about features and performance).