Two things about Mark Shuttleworth's remarks before I go on to talk about the bigger picture.
First: what he said (that Linux is "hard to explain to girls") represented a lapse in judgement, or at least phrasing; it wasn't a deliberate and calculated exercise in dumbassery à la CouchDB. That particular choice of words didn't seem like something Shuttleworth would be particularly invested in, which is why I can't understand why it seems to be so hard to set things aright with a simple "I misspoke; it's not cool to cast all women as technical novices; I'll try to do better in the future."
Second: what floors me even more than Shuttleworth's remarks is the reaction that's come from the community. When you can't even say "Hey, you know, I think we should talk about the issue of sexism in F/OSS" without a crowd of people telling you "OMG, you're blowing things out of proportion, there's no problem, STFU" -- that's a pretty good sign that there's a problem.