Oh yea, and OS=easier to find vulnerabilities.
When the whole world gets to see your code, you can sure as hell bet they will find things and exploit them. Especially when your code becomes quite popular.
To quote Linus Torvalds, "Given enough eyeballs, all bugs are shallow."

This only applies when users are the developers and when they system is updated quickly and properly though...so that doesn't fully apply to trem where developers are gone a lot of the time

If you think Opera is cooler because it's not as mainstream then good for you, that's the same reasons Macs are leetsauce! It's like they want to be OpenSource, but then they don't just to tick you off and not let you have too much fun.
My browser favourites:
Text - w3m
Very compliant (Webkit) - Epiphany, Midori
Fast and clean - Charon
Bulky but with extensions galore (w00t!) - FF3. I liked FireFox 2 better myself, but meh.