Microsoft critics complain about the security and stability of their software. Defenders say all software has bugs, and any software that is as widely used as MS software would reveal just as many bugs. The second part of this claim can't actually be proven, of course, but it is true that even the most beloved software in anti-MS circles has occasional bug and security flaw discoveries.

Whether or not these six flaws in Mozilla (which known MS critic The Register reports under the headline "Mozilla riddled with security holes") are on par with Internet Explorer security holes is dubious, but it does demonstrate that last point. Of course, all but one of these flaws only apply to Mozilla 1.0.1; the current stable version of Mozilla is 1.1, and 1.2 should be out in the next couple of weeks. Nevertheless, 1.0.1 is still widely used (RedHat 8.0 comes with it, and I don't see any official RPMs for later versions).

Whether you care to compare an expired version 1 of a product to version 5 of another product depends on why you'd care. Advocates on any side of the operating system/browser wars want to evaluate the general practices of how software is built and distributed in order to make general claims about their software products, past and future versions, because picking an OS (or even a browser) is a long-term investment. Should the rest of us care? Don't we just want to know what works, what doesn't, and when it'll get fixed? Do you switch operating systems (or browsers) every time you hear about a security flaw in the one you're using?

Mozilla users wanting to feel better can read 101 things that the Mozilla browser can do that IE cannot. I'd like to see a similar list going the other way, though I expect it'd be mostly Microsoft's proprietary closed-standard features, like support for VBScript. I'll let the advocacy folks debate whether XUL is to Mozilla like VBScript is to IE in this regard. :)