I'm sure this all is very true but what does it mean in 'real world' experience?
I guess that I will get at least the same real estate on a 12" rMB (16:10) as on the 13" mba when I go from 'best for retina' to 'more space'. Maybe even more.
That is what's important to me. It's nice to have the possibility to chose more space when I need it, even if it is at the cost of that things will be a bit smaller. The crisp/ sharpness of higher pixel density will make up for that in a way, I hope.
It is just a guess, but I think a 12" rMBA would have the same real estate of the current 13" MBA, which is not bad.
The 15" rMBP has a maximum effective resolution of 1920x1200, emulated on the 2880x1800 screen (220 real ppi, 147 effective ppi).
The 13" rMBP has a maximum effective resolution of 1680x1050, emulated on the 2560x1600 screen (227 real ppi, 149 effective ppi).
If the 12" rMBA has a 12" screen and a maximum effective resolution of 1440x900, then it will have 141 effective ppi, which is in line with the rMBPs available today. If the maximum effective resolution is 1680x1050, it will have 165 ppi, which is not far off.
As for the real resolution, it is still a mystery. There were rumors that it would feature a 2304x1440 resolution, which would be equivalent to 226 ppi, in line with the rMBPs. However, these rumors are silent now.
If the rMBA is to correspond to 4x the resolution of the 13" MBA, it would have to feature a 2880x1800 display, which would account to a 283 ppi screen. It is possible that such screen would drag lots of battery life, and I don't know how Apple would keep the stellar battery life of the Air in this scenario.
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i wonder if the mechanical click goes away..how can you surf in the bootcamp without the click ?
Why not?
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I said it was for comparison sake; it's necessary if you want to compare with other screens that are or would fit in a Mac (we aren't gonna do again the discussion, Apple likely will use a screen at 2x not 1.5x. I might happen to be proved wrong on that, who knows). Of course, you can through software exploit the pixels of the screen different ways, and yes by default the SP3 is at 1.5x.
And of course, if you add to the previous list a 12"@1440x960, I'll agree this could be seen as the most "productive" screen. But, then again, we're down talking about pixel density and comfort of utilization and at 144ppi (equivalent at 1x) we're starting to reach some limits I'd argue (everything almost even 7% smaller on screen than on a MBA11 screen, itself already quite dense): yes the highest pixel density at 216 ppi allow to maintain legibility at small sizes, but there is a limit at going too small or force the user to come closer to the screen (or have to display text larger but then losing the interest of the larger resolution for a larger estate). Microsoft using by default this screen as a 1440x960 screen would be equivalent to Apple making 1920x1200 the default on its rMBP15 (144 vs 147 ppi equivalents).
But all that is not related to the aspect ratio as you presented it first, it's the [software/logic] resolution that allows you to then say it's a more "productive" screen.
I use my 15" rMBP at 1920x1200 effective resolution. I find it very comfortable to use, and have no problems with it. I prefer to have more real estate over big elements on the screen. I understand most people may prefer to use a 1440x900 resolution, but a 1920x1200 resolution is more productive if the person can get away with it.
There are, of course, limits. I tried 2880x1800 on my rMBP, and that is too much.
Used at 1440x960, yes definitely more space than on the native resolution of the MBA11, no debate. That's not what was in discussion. If you're able to cope with a small UI, you could then consider a 11.6"@1600x900 screen is at least as much "productive", although being 16:9. But that's not how I approached the comparison, you also have to keep the pixel density in a reasonable range for 1x usage.
The only way to compare any given [range of] size of screen at any aspect ratio would be at fixed pixel density equivalent ideally, and then you could say a 12" 3:2 screen offers of course a larger surface than a 16:9 11.6" screen (both physically and in term of resolution as we'd be at fixed pixel size).
I don't think I would have any problems with a 12" with a 1440x960 resolution. Not too different from a 13" screen with a 1440x900 resolution. It's 144 ppi vs. 127 ppi. Given that I use my 15.4" rMBP at 1920x1200, it's 147 ppi, so the real estate of a 12" with 1440x960 is OK even for Apple's usability standards.
