So, I decided I would try running all of the demos/tests that could be expected to run with the current state of OpenGL-ctypes. There's a considerable number of working tests (see the "continue reading" link below for more detail than anyone could possibly care about).
What's better, in doing so, I discovered a fairly big clue about the problems with glTexImage2D, namely that the problems do *not* occur if the texture-loading is delayed long enough. It appears that something about how I'm setting up the texture creation is trying to create textures without a valid current context. Will have to look into that next time I'm playing.
I spent a few minutes trying to get the glMap2[df] functions working. No go there; I seem to be messing up on calculating the strides and orders from the input array. No errors show up, but no pretty pictures either.
Anyway, think I'll check the current code in and try to stop thinking about it... still hoping for the elves to fix the code while I'm asleep :) . For the curious, the list of what demos/tests are currently working: