Do You Trust Microsoft?

Many people don't, while others are not so cynical. Reading this story, I have to wonder what MS is thinking. This is scary stuff. You install a Windows security update and end up with a Firefox add-on that can only be removed by modifying the registry.
Security Fix - Microsoft Update Quietly Installs Firefox Extension

A routine security update for a Microsoft Windows component installed on tens of millions of computers has quietly installed an extra add-on for an untold number of users surfing the Web with Mozilla's Firefox Web browser.

Earlier this year, Microsoft shipped a bundle of updates known as a "service pack" for a programming platform called the Microsoft .NET Framework, which Microsoft and plenty of third-party developers use to run a variety of interactive programs on Windows.
...

Annoyances.org,
which lists various aspects of Windows that are, well, annoying, says
"this update adds to Firefox one of the most dangerous vulnerabilities
present in all versions of Internet Explorer: the ability for Web sites
to easily and quietly install software on your PC." I'm not sure I'd
put things in quite such dire terms, but I'm fairly confident that a
decent number of Firefox for Windows users are rabidly anti-Internet
Explorer, and would take umbrage at the very notion of Redmond
monkeying with the browser in any way.

Big deal, you say? I can just uninstall the add-on via Firefox's
handy Add-ons interface, right? Not so fast. The trouble is, Microsoft
has disabled the "uninstall" button on the extension. What's more,
Microsoft tells us that the only way to get rid of this thing is to modify the Windows registry, an exercise that -- if done imprecisely -- can cause Windows systems to fail to boot up.