How well-rounded are you outside of computer programming? Hard sciences, humanities, etc. I ask the question because to me it seems like hyperfocus is a significant danger to the unschooling concept.
In particular, I can see a real possibility that an unschooled child with a heavy computer focus and a lack of parental guidance could very easily lock in on computers and neglect potentially "boring" but incredibly helpful topics. I'm thinking largely of the humanities here; you can get away without understanding, say, chemistry [1], but it seems difficult (in my circles, at least) to be taken seriously without a decent command of English--a skill that I think is refined largely from reading, because I've never met someone who could speak and write well who didn't enjoy reading--and it seems like it'd be difficult to really understand the world around you without a decent grasp of history. In neither case does Wikipedia really cover it; I think that a level of internalization of such things is necessary (it becomes harder to evaluate political statements without at least a high-level understanding of where they come from, which has driven my own recent forays into economics and sociology).
For similar over-focusing reasons, I'm generally but not completely skeptical of the "don't go to college" argument sometimes espoused here on HN; the focus on matters of immediacy--the get-a-job skills--strikes me as a good way of turning out someone with a few strong skills in a few areas and a generally fuzzy understanding of topics unrelated to their focus area. I am, however, even less fond of the idea of "max out your subject matter, take the bare minimum outside your degree area"--I have a hunch that a self-directed person is more likely to stumble into well-roundedness than somebody whose academic drive is constrained to do-your-job topics.
[1] - Not to say chemistry's a useless subject by any means, I actually draw on it sometimes in my day-to-day life. But knowledge of the hard sciences, physics possibly excepted, are a little less impactful overall.