Did you notice when you posted that that you also fried the entire premise of the linked article? Work still beckons, email still beckons.
If it is left up to the user to not permit those things to beckon, well, gosh, I can do that right now on any machine I choose, there's nothing special about the iPad.
There is no such thing as "work machine" or "personal machine". There are only computers. Turing machines. A computer is what you make of it. In fact I'd fight anyone who tries to hide this fundamental mathematical truth, because they're probably trying to lock me in a trunk. Which in fact Apple is. (The metric works!)
Not only is your definition of a computer narrow, it's not even accurate with regards to the iPad.