The issue presented here isn't microsoft, its Apple. its about apple's iTunes product being sub-standard quality. And thats that.
And tens of thousands of users having the same problem (and having it be reducible in 2 or 3 days to a repeatable problem) means that there was little to no testing done. Part of testing is USING the myriad environments of the ecosphere in which your application will exist. It would be like writing a web phone app that only works at 120 x 160 but crashes at 128x128. Sure, it doesn't crash on EVERY phone, but it crashes on a significant number of them.
(It's unclear to me, by the way, that your claim that only a few systems crash is true. I'm able to reproduce the error bug by doing a clean install of iTunes 8. It seems like the problem is much larger than you want it to be. But even if I concede your point that it's smaller than everyone, it's still large enough that we're seeing 'software malpractice')
And Microsoft got hip to how bad the "but there's lots of systems, wahhhhh" excuse is. Welcome to the 21st century. Apple should get hip to how lame that excuse is, too.
Also, your "TENS of THOUSANDS" of people are a frigging drop in the bucket compared to the TENS of MILLIONS (or possibly even HUNDREDS) of Windows systems currently in deployment in countries where Apple distributes their products.
Don't people constantly defend Microsoft with the same argument -- namely, that they have no way to test every possible interaction between bad drivers and hardware components simply due to the sheer number and variety of Windows systems in use at any given time?