Federico: Yeah, the state of ISV support in Linux is pretty sad, but your first point, “One-size-fits-all RPMs that don’t work? That’s because distros install stuff wherever they damn well please.” isn’t really the crux of the issue. It’s way worse than that. The location on the filesystem isn’t really a problem. By and large most distributions are following a fairly sane scheme, and even ones like SUSE which put GNOME in /opt/gnome are smart about looking in /usr these days. Love it or hate it, the FHS and diligence by the distributions has made this problem largely nonexistent. The real problems with RPMs are that there aren’t coherent packaging conventions between distributions and that you can’t rely on a particular consistent runtime across all the distributions. Not that I can really blame them. Who wants to guarantee that python 2.2 will be available everywhere for all eternity?
Vendors like VMware that ship kernel modules are even worse off. The kernel is basically a library, only unlike real libraries, you can’t have more than one version at a time. And the fact that most Linux distributions patch the hell out of their kernels doesn’t help when trying to target a consistent runtime.