[gumby]

It’s so tiny it’s practically the size of an iPad. If you travel a lot this can be a huge deal. I did a ton of development on one and it was great, but I had a beefier machine for visualizations and big compiles. Still, the tiny 12” is my go-to computer, small disk notwithstanding.

It also appears anecdotally that the smaller screen is more popular in Asia than in US/EU (for both Mac and Windows).

[athenot]

I used to have the 13" MacBook Air but am now on a 15" MBP. What I found is that whereas I'm reluctant to pull out my MBP on the couch or bed; I used to do that without hesitation with the MBA. There seems to be some threshold of weight/size that produces friction and makes me keep the MBP on a desk instead of using it like a (more) mobile device.

This is bizarre since the 2 machines are not immensely different in sizing, but it's something about the feel. Obviously this is highly subjective but this is making me consider a 12" MacBook to have as my personal, non-workhorse machine.