Ralf, thanks for the comments. The scientific community is definitely the key group that *need* mingw (as opposed to people who merely want to use it because they don't want to buy into MS compilers, or for similar personal reasons).

My personal view is that if the scientific community comes up with a mingw/gcc toolchain that they are happy with, and willing to support, then I would see that as a reasonable target to be "the" supported mingw toolchain for distutils.

I'd like to see a single-file "download, unzip, and use" distribution rather than the current rather intimidating set of instructions on how to set the toolchain up - but I'm sure that's part of what you're intending to cover under "ensuring long-term maintainability".