I think it's a mistake and a dead end, frankly. Apple did an admirable job of condensing their desktop UI down to something that's actually usable on a 9cm touchscreen, but attempting to remodel the desktop UI that already works just fine to make it more like the fun-size clone is just stupid, especially when desktop/laptop computers have not (and are not going to) lose the real versions of the input devices iOS had to be adapted to make do without.
That's also why I think tablets are a dead end, they're just an attempt to copy a UI paradigm for devices that are too small for the normal, time-tested approach to devices that are hardly any smaller than a sub-notebook computer, where those limitations are not inherent. I blame this on the general stabilization of desktop UI; Apple used to make their name on revolutionary usability, but it's hard to keep coming up with new improvements that are really improvements after 25 years of GUI ubiquity, so they've decided they want everybody to pretend that the iOS user interface is more than just a decent compromise given the hardware limitations.
One of the first things I noticed when my brother got an iPad is that he also has a Bluetooth keyboard for it, and well more than half the time he's got them both installed in a leather case that makes the whole affair into a poor man's laptop. I guess I can see the appeal of touchscreens for people who (as most do) don't really think much of touchpads, but aren't comfortable with keyboard-centric navigation, but why not simply integrate touchscreens into laptops and cut out the middle-man?