You need to check again. Higher resolution screens consume more power. No if's about it.
The new MacBook is no ultrabook. It has CPU performance on-par with the i5's from just a couple of years ago - in other words the type of computers that most of the world is working on.
Yes, the DO consume more power. But under day-to-day tasks, the battery hit will be relatively small.
As for the new rMB, even if we leave the performance alone (which is only borderline acceptable for a $1300 2015 machine), we are still left only one usb port. But anyway, I guess what I wanted to say in my previous post with that 'netbook' statement, is that the performance doesn't go hand in hand with price for it, in other words, rMB is more of a fahion accesory, not really a device to replace your ultrabook.
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To add to this reasoning: look at the price of the base model MBA. It's the only Mac Laptop with a sub-$1000 price tag. If you add a retina display, the cost goes up to, well, the MacBook/MacBook Pro level.
I think the Air might stick around for a while, but will be intended to be the entry level Apple notebook. And, entry-level notebooks get entry-level displays.
To my mind, it actually would've made more sense to swap names: the new ultra thin laptop would be the new "MacBook Air," and the non-retina (not as) thin laptop should get the "MacBook" name going forward.
You got it all wrong.
new rMBA takes over the rMBP 13" and it's current price and all the extras like force touchpad and more storage/ram.
non-retina MBA line stays alive (couldn't hurt to bump the resolution to 1680x1050 though and make retina-like bezels).
Then we have rMBP 15", where the name "pro" in it actually means something (not like the current 13" rMBP, which is slower than MBA when using in it's retina native resolution) and seems logical.
IMO that would make much more sense than killing the current MBA line.
PS.
It has CPU performance on-par with the i5's from just a couple of years ago - in other words the type of computers that most of the world is working on.
If we are talking ultrabooks - 4 years, not 2.
2011 ultrabooks scored on Cinebench quite similarly to the CPU used in rMB but tested in active cooled environment (Yoga 3 Pro). It's still not a bad perfoemance, considering that back in 2011 these ultrabooks were truly one of the kind and this certainly should be enough
if the CPU is not throttling, but not for $1300. With this price tag, like I said, it's a fashion accessory.
EDIT once again: That all being said, I still don't think that it will be able to play UHD youtube videos without lagging. It will be more because of the poor youtube html5/flash player optimization, but still, consumers won't care about the reasoning.