Okay. I just came in here to say that there's no so such thing as Firefox 6.0. We're still on 4.2, and fuck you if you say otherwise.
Especially if you work at Mozilla.
Seriously Mozilla. I love you guys, and Firefox is totally my browser of choice, but why, out of all the things you could have blatantly stolen from Chrome, would you choose to steal their absolutely batshit insane version numbering system? That's stupid, and you're stupid for having done it.
Anyway, to say something on topic about the actual study: Duh. I've tried out IE9, and I still prefer Firefox, but the simple fact of the matter is that IE9 has always been a pretty good browser. It's faster than people think, it's safer than people think, and it's just generally made fun of because "M$ R EVAL!!1!" or "IE6 was terrible, so IE9 must be too!"
Am I recommending IE9 to anyone here? No, of course not. I believe that people on this site tend to be of the kind that can really make use of the more advanced customization options of Firefox and if you're using Chrome or *shudder* Safari then you've bought wholesale into those corporation's sales pitches and nothing I can say will ever reach you. (Okay fine. Chrome has some legitimate points in it's favor. I don't like it, but maybe you have a good reason to use it. I just think the cult of Google is starting to get almost as creepy as Apple cultists. Sorry.) Anyway, my point was that we (particularly those of us reading a thread about web browsers) don't represent typical internet users. Typical internet users could do far worse and not really any significantly better than IE9.