What about the none open source apps? If microsoft is ever going to be relevant again, they have to make it worth developing software for Windows rather than webapps. Microsoft has some advantage, since their apis are much more powerful than html/css/javascript, but actually getting users to install your program, and dealing with all that crap makes it not worth it.
So right now I have msys + mingw + msysgit + emacs + console 2 on windows 7 and xp for development. It was difficult to set up and I'm happy that it is fully functional. I am actually a bit surprised that I got bash and emacs to a point where I'm happy. I can do what I need to do to deploy my application on windows with nsis. Or since the main part of the program is in python py2exe + nsis.<p>I can already get to the point where my application is an msi or exe or zip. What is CoApp going to add to the equation?
It is interesting that Microsoft is involved with this. One of the developers is being paid to work on this project full-time.<p>Now if there were something like this for device drivers...
Also useful is WPKG: <a href="http://wpkg.org/" rel="nofollow">http://wpkg.org/</a> Though it isn't exactly the same idea (more related to multiple workstations).