Very, very sound advice. I can't tell the number of hours I've spent playing around with browsers. I'm a better webmaster for it, to a certain extent, but the time comes when you just have to get down to work. I love Opera's look, but its features can't compare with the developer tools for Firefox. So I use Firefox with the Opera theme! ;)
Not always true. Opera's speed seems largely dependent on caching, which, by default, it does quite poorly (you never can tell if you're seeing the most recent version of the page, even after a refresh). For first requests, Firefox is just as fast with pipelining enabled and nglayout.initialpaint.delay set to a low value.
<joke> Firefox will always be better than Opera, just as Chevy will always be better than Ford and Pentium better than AMD. ;) </joke>
To be brutally honest, Google and Firefox are playing around together these days anyway - it's not just Google and Opera. The fact is, if you're going to use a mainstream browser, its time to kiss privacy good-bye.
That is a very good point. Firefox has a solid, committed marketshare. Personally I don't think a free Opera will make much of a dent in it, but it will certainly slow Firefox's growth. The issue here is, do you want many challengers to IE, no challengers, or only one challenger? Some see diversity (many browsers with equally large marketshares) as the best thing. I'm sure others would prefer that Firefox be the only challenter to IE. Personally, I'm on the fence on this issue. Another point is, how large can the total non-MS browser marketshare ever get? If the current 20% is all, then there's really very little harm in breaking it up between several browsers.
In the end, Opera without the ads is still Opera. It's got a slimmer interface, but I still just find it clunky. My idea of a browser is about the same as a good mountain bike - it should be as quiet and intuitive as possible, and should be the last thing on your mind while you're using it. For me, Firefox meets that criteria better than anything else. No doubt Opera will do it for others. The advantage of Firefox is that its far more customizable. The advantage of Opera is that it does more out of the box. That's a big advantage to people who have other things to do than just play with their browser! ;)
One thing is sure - we're now seeing Opera and Firefox compete on more or less equal terms. Firefox has the upper hand at the moment, but now that Opera is free, I predict we'll see the sparks start to fly any time now. I'm rooting for "The Fox," but the battle should be interesting to watch.