Hybrids have a very different audience compared to regular laptops (ultrabooks), as they're structurally very different (that is, they are a compromise by definition), so I wouldn't compare them directly.
Don't get me wrong, I have one instead of a regular laptop, but I can see how people used to the latter would feel uncomfortable with them, unless they have a strong motivation to move to the hybrid form factor.
> Hybrids have a very different audience compared to regular laptops (ultrabooks)
Ultrabooks/Subnotebooks are already a compromise. We've made the transition from massive 30-40W CPUs to 15W-CPUs for mainstream notebook over the last 4 years, where net performance for notebooks stagnated at best (and regressed during the first year or two). Going from there to whatever hardware the Surface Book uses won't a big leap any more.
To me it's not a question of CPU power, but form factor and user experience. Hybrids have for me two big drawbacks --- and it's really subjective:
- I like small tablets and larger laptops (13.3 min, 14 prefered). So an hybrid is either a too big tablet or a too little PC, often both;
- hybrids are top-heavy, and I don't like having an hinge. I really want a LAP-top, and a ultrabook is perfect for this. An hybrid, not so much (I've heard about "lapability", not convinced ;).
Both are intrinsic trade-offs of hybrids. So I stick to small tablets + 14" ultrabook, and just don't bother with hybrids. But to each its own.
Academic definitions aside, there hybrids have to choose a very serious compromise due to the balance:
if you make the base light (surface pro case), you won't really have a laptop, instead a tablet which sits on your legs.
if you make the base heavy, you're making a relatively heavy laptop.
now, there is of course a spectrum of choice, but practically speaking, even they make a very light tablet part (say, 850 grams), with a "heavy base", you will add 550 grams at least (550 being an odd balance).
I'm absolutely happy to have a 1.4 kg hybrid, but it's not going to compete with the upcoming wave of ultrabooks (note that I'm somewhat skeptical it will be 1.4kg, I bet it will be a little more).
Update: they've just published the spec, and it weighs, as I was suspecting, 1.5kg, which is not bad for a sturdy (I assume it's going to be robustly built) hybrid.
I have a bay trail asus T200 which is a similar, albeit low-end, device.
The problem for me, under Windows 8.1, has been getting the machine to enter a true low power sleep state. If the machine enters the true low power state than it can work like a tablet, and if you use it lightly (say an hour a night) you can get a week's worth of use without recharging.
Unfortunately if any of the hardware components doesn't go to the low power state, the device will likely be dead or close to it if you don't use it for a day. Microsoft has a utility which tells you which component is keeping device from powering down, but doesn't tell you what software is causing this behavior. Windows 10 is supposed to improve this, but you can't turn off windows update so you lose one way to fight the battery drain.
One way you can fight this, besides plugging it in every night, is powering it down when you are finished, which isn't as bad as it seems because the device boots cold in about 5 seconds.
Don't get me wrong, I have one instead of a regular laptop, but I can see how people used to the latter would feel uncomfortable with them, unless they have a strong motivation to move to the hybrid form factor.