They're framed with that assumption because of the other articles that call it "the future of computing". If something's the future of computing, it's supposed to supplant the present of computing, right?
And people definitely don't go and watch plays and operas live anymore now that they can do so in their living room with a TV.
You need a better dictionary..
Anyway, I was merely illustrating that "the future of" does not mean "the sole replacement of".
Motor/Steam boats are now used where Sailboats were used, 100% of the time.
TV/Movies have replaced Opera/Theater for mainstream entertainment.
For me, as a developer, the ipad certainly won't be much more than a diversion or a target for development. For people like my wife, though, I think it will definitely have an impact. Many people simply want a content consumption device (web, media, etc), and I think the ipad is a very good device for consuming most content.