Package managment system for Windows?

Sadly, we are still living in a time when software companies expect that we will have all their software on disks that we bought from a store instead of conveniently downloading them off of a file server. Although I think Windows definitely has the built-in technology to do something like this. Instead of using Windows Update to simply download Security Patches, wouldn't it be nice if it had useful stuff too? I guess you could also think of Steam as a sort of package system, though it only handles Half-Life mods and other games. I think the biggest problem with getting a Package system built into Windows is that you'd have too many competing companies with software in it.

Jam it back in, in the dark.