Desktops are dying on their own, they'll survive in offices and as cheap alternatives to laptops. Microsoft introduced the tablet as the replacement for the laptop, Steve saw it as a product BETWEEN a mobile phone and a laptop. The days of one computer per household or person ended back around turn of the century. Virtually all tech people have a smart phone, tablet, laptop and desktop. Each has it's strengths and drawbacks.
I have a standard Mac keyboard I use with my iPad. Bluetooth pretty much just works. I can do work on the tablet when I need to. But it's not a replacement for any of my other gadgets. It's brilliant when you want to explain something to someone on the fly, check your stocks or play angry birds.
That's just the talking point of tablet junkies, they're totally going to kill laptops and desktops dead, any day now even. Just you wait and see!