to all those monkeys here that do not understand the needs of others. Just cause you don't need 17" screen as you can use your 13" with external monitor doesn't mean that we all have the same option! For crying out loud if I could always connect the external screen then why would I even bother with a laptop? I could get mac pro and get all the power I need and have all the screen space I want with as many screens as I need!
To me, 13" is ridiculous computer. Too small to do anything yet I don't come here bashing everyone around just cause your model sells more! There is a lot of people asking for 17" and those people ask for a reason. They don't invent their desire and they do have needs for it so why do you keep coming and bashing them for it? I want and need 17" for the screen estate. I have 15" and its just damn small. No, I can't plug in external screen everywhere I go! If I was like everyone of you then I would be coming here and saying that I hope they will discontinue 13" and 15" so you can all use fricking 11" MBA! Now lets see how you would like that when your NEED is different!!!
For crying out loud, leave the people alone. There are people that actually need 17" for a valid reason so stop attacking them! Be understanding that there is a group of people that have different needs than you! Yes, 13" is fine for facebook but those that need 17" are in a different software group. In fact, try to do anything in Maya on 15" for extensive period of time and let me know how that goes. Having just graph editor, hypershade, outliner and perspective view + shot view open. Then come here and boast how great the 13 or 15" is great for anyone!
I don't think many people are trying to deny your right to choose the tools you need, although admittedly there are those who have almost religious fervour to "convert" everyone else to their particular preference.
There is no doubt that working on a larger screen is more productive for most tasks - many studies have shown that two 22-24 inch monitors are optimal for common productivity tasks, and some people prefer 3 or 4 screens. If you are really stuck with only a laptop (e.g. you're a travelling musician, stage manager, service engineer, or someone who doesn't use a computer on a desk ) then I can see that having a 17" screen could be useful.
The problem is that this kind of computer is not what Apple wants to associate itself with these days. Thin is "in", and pushing a 7lb (3kg) laptop isn't the image that Apple wants to sell, even if it's really useful for many people.
Apart from screen size, Apple no longer makes "desktop replacement" spec machines. Quite a lot of my colleagues have 32GB Lenovo W510s (which come in 15" or 17" screens & can fit 3 SSDs) and these are pretty good developer machines for those who have to travel.
Apple simply doesn't play in this market any more.
My solution is just to have a load of external monitors (I have about 4 screens at work & home). They are cheap enough ($100-200) to just leave wherever I need one. You can often plug in to HD TVs in hotels these days, which isn't too bad.
If we think about it, the future of computers must find some kind of solution to the physical size limits of laptops. We probably will end up with very small computing devices (or terminals into some kind of cloud computing resource), that will project video to display devices - maybe "glasses" or a HUD, or even simply an development of the meeting room projector. We can already use AirPlay to display our laptop / iPad screens on an HD TV, so why not develop this idea, and have a computer the size of an iPhone?
I don't see the keyboard and some kind of pointing device going away for some time, but display technology is likely to evolve into something more physically compact whilst giving us a larger virtual desktop.
