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This all looks very good. I hope it will gather acceptance someday soon (since this project will be worthless unless people actually make packages for it). I am convinced that this is one thing that Linux REALLY needs to succeed on the desktop. I also just wanted to acknowledge that this is HARD stuff. I think a lot of people don't realize how fragmented the current situation is.
Systems that rely on repositories (RedCarpet, apt) work great for free stuff (as long as the repositories are well maintained). However, for non-free software, these systems are worthless. Linux NEEDS a system where the software developer/company can distribute applications generically rather than per distro. Otherwise, getting commercial application support is going to be very difficult (and will likely be limited to the major distros only).