I don't think the opportunity is lost, it's just that none of the big companies are taking advantage of it.  Honestly, I think that's because they think it's too hard.  Microsoft and Apple have been trying for decades at this point to make a computer that's open, easy to use for everyone, never crashes, etc.  The open source community has been trying too.  I don't see anyone as having succeeded there.  It's not for lacking of wanting to succeed, or for a lack of trying, it's just a <i>really hard</i> problem, and by locking things down they can create things that work much more predictably and reliably.<p>I don't think the OLPC is a counter-example; it solves some issues in virtue of having a standardized hardware platform, and they've tried to do away with the file system (which sort of works and sort of doesn't), but I don't think they've completely solved all the other problems around versioning and installation and removal and viruses and third-party devices that need their own drivers, etc.  I don't know a ton about it, so it's entirely possible there's something else innovative there that I'm missing.  I also would argue that they haven't done it in a device that an average consumer would really want.  They done all sorts of innovative things that I think are great, but I don't think they've solved those fundamental issues in a general way.<p>As for the moral obligation standpoint . . . I haven't read Zittrain's book, so I can't fully debate that argument.  From my perspective, roughly, you have a moral obligation not to do X if doing X infringes on someone else's rights without their consent.  So to say it's unethical to create a device like the iPad you'd have to argue that people who don't buy the iPad are directly harmed by it somehow, and that just seems like a tough argument to make.  I think the effect of something like the iPad on the future of computers, the internet, society as a whole, etc. is so hard to predict that I don't think you can fairly say that someone or some company has a moral obligation one way or the other.  Maybe those devices will open up computing to people that currently couldn't use those devices, making their lives better.  Maybe it will enable doctors to carry around a tablet that helps them avoid mistakes, saving lives.  Maybe it will help small-time developers make more money selling their software.  Or maybe it will kill innovation and put us at the mercy of an increasingly-paranoid government and law-enforcement community or put our information and privacy firmly in the hands of large corporations.  It's so hard to say which way things will go that I just don't think you can say it's unethical.