Afraid I let the ball drop on this one. What with Red Hat producing developer-focused LiveCD's, and Toquito planning to produce them, I considered the question of a 5-minutes-to-a-development environment issue to have been solved.
But it seems we haven't had an updated developer's LiveCD in about 4 months... and the LiveCD wasn't great as a development environment anyway. Over the past few months I've tried (and failed) to update my Gentoo developer's environment a number of times. I've given up on trying to get the environment running under Gentoo until the APIs stabilise.
So, it looks like what we need is a Fedora 7 VMWare/Qemu image that has a sugar-jhbuild environment. To make it useful, we'd want to have it getting updated every day or two. To make it ideal, we'd want some customisation to cut out extraneous software and reduce the total download to a CD's worth or so. All of which is not really something I can do alongside trying to write an IDE and recruit developers on my 10 hours/week.
So, anyone want to become a Developer's Image Maintainer? Your mission would be to develop and maintain a Sugar developer's image such that developer's on any of Win32, Mac and Linux (any reasonable flavour) can download the image, unpack it and be able to begin development within 5 minutes. The image should have tools suitable for developing in Python and/or Smalltalk from a GUI desktop, preferably with a GUI IDE with a direct link from the desktop as a default suggestion for how to get started coding.