Package Manager for Windows

ideas tagScreenshot of a typical Windows installerIf you’ve ever used Linux, you probably stumbled over the great concept of package management. When Microsoft revised MSI (now called [url=]Windows Installer[/url]), they failed to include the simple mechanism for applications to register at a central update management. The crucial point is that while Linux repositories mostly contain GPL software that can be easily packaged by third parties, a Windows package manager needs support from each individual developer – which is not going to happen any time soon without Microsoft stepping in.
I am certain that the Windows world is ready for a “Web 2.0 solution”. In times where all our [url=]knowledge is being collected for free[/url], people might actually use install scripts supplied by a community, without direct support from the vendor.

The vision:
[list][*] install scripts based on macro recording ([url=]AutoHotkey[/url]) and scriptable installers ([url=]NSIS[/url])
[*] community review with different stages similar to Linux (“testing, unstable, stable, …”)
[*] decentral distribution of both scripts and, optionally, installers/updates themselves (eg. based on Bittorrent)
[*] open API for programmers[/list]
Extras that come for free:
[list][*]community based recommendations (“if you’re looking for a burning tool, why don’t you try…”)
As a programmer, why do I have to reinvent the wheel every time and add mechanisms for installation, update checks, download and upgrading to each of my applications individually?
If you look for existing package managers, there’s already quite a bunch out there (which wasn’t the case a few years ago). But, if you look closer, nothing comes close to a real [i]package manager[/i]. Many tools only offer plain version checking, others offer a very limited repository. A few look promising. Why did they fail? Can we do it better?
I have sorted the links based on my first impression, the top links going to the most promising solutions.