I'm buying one for my 3-year-old. I can see several advantages to this approach over other laptops. First, I can give her a rugged computer that actually works, something she will surely like as she sees her mom and I using our laptops all the time, and kids learn a lot by imitation. Second, I can continue teaching her about philanthropy - we bought one for her and one for someone else who could use one but can't afford it. Third, to counter the arguments about the US educational system ignoring the OLPC, education begins in the home.
As a programmer, I look forward to seeing the software efforts that are built atop this platform. There's plenty of room for free educational software for kids and this looks like a good platform for it. Surely someone will port the platform stack to a standard Linux distro, and then any software you write for this, you can run on your PC you bought at Wal-Mart.