I was actually pretty disappointed with the "beginner" workflow for the Raspberry Pi, which is essentially "run this linux distribution, which has some educational applications pre-installed once you fire up X". Not to knock linux, but based on the stated mission of the RPi, I would have thought something more similar to the traditional 80's experience of "boot & start programming" would have been the out-of-the-box default.
I've actually been mulling over starting a project like this for machines like the RPi and APC -- an OS where you basically boot into something like a REPL, and start coding away.