Personally, I despise non stand form factors. I'm a chronic tinkerer and if I can't alter it I don't want it.
Thing is, you're a dying breed, unfortunately.
But an all in one system? What if the keyboard goes bad?
Err, by all in one, I was talking iMac or similar - where the computer is built into the screen, not the keyboard. So in the case of "what if the keyboard goes bad", the answer is "buy a new one".
Having the computer built into the keyboard might be kinda cool and quirky in the retro sense, but it is a form factor that comes with too many compromises, even against iMac style systems.
What about the other parts? I may have a choice of hard drives and the amount of installed memory, but everything else is built in.
So, no choice of video or sound cards. No expansion bus to add accessory cards.
Basically, once its obsolete I throw it out.
Unless you're a gamer, or someone who has a specific need for a particular addon card, or in your case, a tinkerer, there really isn't the need for a honking great tower system, the vast majority of computers sold to consumers come with integrated everything and never get upgraded anyway, hell a good few of them will get dumped simply because of virus infestation rather than anything being wrong with the hardware...
That might work for business. They rarely upgrade rather then replace.
An all in one computer doesn't suit me and never will.
You != Average computer user.
Micro ATX is beginning to make sense as many of the components that had to be added by cards are now commonly integrated into motherboards.
The vast majority of systems sold in towers these days are MATX. They're cheap to produce, offer good enough graphics and sound, but again, unless the owner is like you or has specific need for a specific addon card or is a gamer, chances are that board will never, ever see an upgrade. Then again if you're a gamer chances are you're not going to be buying an entry level system which make up the majority of all PC sales.
But I really don't believe that the keyboard computer will ever dominate.
It won't, but all in ones of the type the rest of us are talking about - IE where it's built into the screen - the so called "lifestyle PC" probably will.
The netbook market has pretty much dried up as the emphasis on small cheap computers has moved to price ranges above entry level laptops, at which point it gets harder to justify the costs.