No. Bad coding should always result in bad publicity. Microsoft seem never to test their stuff - with their budget bugs like this are absolutely inexcusable, and a prime example why their monopoly is detrimental if not debilitating to the computing scene.
I hardly go around defending MS all the time, but I disagree with you here.
This is a fairly obscure vulnerability, even though it appears simple. But, as with many things, the "solution" appears simple once it has been found. Many other vulns have been found in IE6 SP1 since it was released late last year.
Microsoft do have an awesome budget at their disposal, but I don't think it's QA that is the problem here, it's that functionality is regarded as a far higher priority than security, reliability and performance. The last three factors do not directly earn MS money. Functionality is something definite that can be heralded by their sales/marketing reps. Security, reliability and performance aren't anywhere near so easily marketed.
If people honestly judge Windows, it should be admitted that Windows for example is a fairly awesome product, and in many respects far ahead of the competition for the audience it is primarily aimed at (average desktop users). However, its main problem is that, a bit like with Netscape 4x, true innovation has plateaued. What is needed is for it to break out of that mould, which to a certain extent in the case of Netscape 4x, Mozilla did, and Firebird/Thunderbird has done also to a greater extent. However, "breaking out of the mould" for a business is risky, and while in long development, doesn't earn them any money.