Well, when a person feels he/she is 100% correct on any subject, then they are stupid. The correct thing is to ask "why do you say I am wrong?"...but few people do that.

First a nit-pick. It's not telling them they're wrong, it's merely expressing an opinion.

But no, I'd doubt that it's a surprise to anyone that people feel insulted by such things.

Nope, at least not according to my religion. Would it be fair to punish someone just because he or she didn't get to know you ?
Maybe he of she needs to learn some other lessons first or is in some other way not ready yet.

I don't understand your nitpick. If I opine X and you believe not-X, doesn't my opinion imply you are wrong? Is there really a useful distinction to be made between saying "X is true" or saying "If you believe not-X, you are wrong about X"?

But unless there can be, and not be, a god at the same time, then believing there is no god means you believe the people who believe there is a god are wrong.

What I mean is, if you don't believe those people are wrong, then you believe you're wrong. If you don't believe you're wrong, then you believe they're wrong. It's nice that you're open to the possibility that you may be wrong, but that doesn't change that you believe you're right and they're not. You can't both be right.

You forgot one option: you don't know for sure if something is true or not. For example you can't be 100% sure that timetravel is impossible. Who are wrong, the one who believe its possible or the ones who don't?

Actually, I get tired from this whole stranglehold discussion.
Sure, a de-facto monopoly like the one Microsoft has is a bad thing. Still, for Macs, the situation is even worse, since the company that makes the hardware is the same that also makes the OS; and I'd estimate the market share of MacOS in the mac sector a lot larger than that of Windows in the PC sector. Yet nobody seems to complain that Apple has a monopoly on Mac operating systems. (OK, you can use Windows on an Intel Mac, and quite some people do - but even before that, almost nobody complained).

What bothers me more than the fact that there is a monopoly, is how microsoft abuses this position to push non-secure, buggy, non-standard software into the market in order to extend the monopoly over other realms (e.g. browsers).

I get the idea that Apple still makes (mostly) good software, while microsoft abuses its monopoly to get away with inferior products.
A monopoly isn't a bad thing in itself. The problem is that too much power rests in too little hands, much like in a dictatorship or monarchy. A monarchy with a good, wise, and unselfish monarch is in fact the "ideal" society form. Unfortunately, good monarchs are rare.
Apple isn't a Good Monarch either; they too abuse their position. For example, after they bought emagic, they stopped development of the windows version of the Logic product family - the best music production tool I have encountered so far. The only reason to do so was to force studios to stick with or buy Macs, by artificially penalizing PC hardware in the competition.
Still, their software seems to have less bugs, look prettier, and be more ergonomic in general, than their microsoft counterparts (excluding Word, which should be the microsoft flagship instead of windows).