OSNews

Windows Update has pretty much *nothing* to do with the package managers: it covers ONLY the update of what MS wants to update, and even then only of the software they provide themselves.

How do you know a new version of your ApplicationX is out? How do you upgrade?

On windows there are only 2 ways (that I know: if you know better, please tell me. I've been searching for it for ages now).

1 - You spend time going to the vendor site or to some windows software website (normally caotic and full of banners, popups and whatnot), and discover (who knows when) that a new version is out. Then you download it, and figure how to upgrade: will you simply launch the insaller? Will you need to uninstall before, and then reinstall? Who knows. It's not normally written anywhere. Then maybe you reboot your machine. Repead xNumber of software involved.

2 - The application itself checks from time to time if a new version is avaliable. This is a horrendously inefficent way of doing this, and means a lot of softwares can call home whenever they want. Plus, they often install service like applications, maybe even placing annoying icons in your already crowded systray.

On Linux?

yum update

I read what's new, and then press Y. Done.

Want Gui? Click the icon in your notification area, take a look at the new versions, then press "Update". Done.

On a deb based machine?

apt-get update
should keep you ok. Done.

Don't bring package management in a discussion to say windows has some advantage: I am a sysadmin and would thank the gods for something as simple and powerful as linux package management on windows.
And no, the third party solutions or AD (both costing thousands of EURs) do not count. Besides, they normally need another person doing the legwork.