I don't think the title is misleading. He spent over half the blog talking about how you don't have access to POSIX tools on the iPad. But the iPad isn't a Unix

I don't think the title is misleading. He spent over half the blog talking about how you don't have access to POSIX tools on the iPad. But the iPad isn't a Unix. It's only when you jailbreak it and add the unix tools do you even get to a commandline. There are many applications that are GUI based and do good message passing. But they are on the desktop the iPad isn't that. It may share the same underpinnings as OSX but it is not a desktop bound OS, it is an appliance. He doesn't like the sandboxing but the sandboxing is also why it is secure.