My prediction...
I don't think the PC market is going to die, there will always (for the foreseable future anyway) be a need for desktop PC power and processing in science and business.
However I think the performance PC market will continue over the next decade (deservedly, imo) to become increasingly niche to the point where only a few main companies are left to provide performance components. As consoles, phones and tablets continue to increase exponentially in power it will make PC gaming increasingly and more inevitably redundant (though many seem to keep fooling themselves into thinking this won't happen), and only the main powerhouse development houses will be left, and even then the vast majority of titles will be multi-format (few developed as PC-only, and even then only major big-seller franchises).
Tablets are so popular because they fulfil the majority of peoples simple computing needs... browsing, basic (though increasingly advanced) gaming, social networking... it's only when you start to get into more specific usage such as graphic art/design, advanced gaming and all the more intensive and accuracy-demanding tasks that a tablet falls short, and will do for a couple of years yet.
However, the ASUS transformer has already shown us how a tablet can function as a laptop even in its basic state, and as power starts to get serious then we will see the tablet eventually evolve to fully replace the laptop as an all-in-one device that can be attached to a docking station to provide a laptop experience, or removed to have the full sleek tablet experience. In conjunction with a games console (which I also believe will become increasingly irrelevant, but a fair bit further down the line) and Smart TV I don't think there will be any real need for a home PC down the line for anything other than an increasing minority of specialist users.
Phew.
at no point did I say either machine was better or worse than the other.
