Verge crew's MacBook selection

If you've paid attention to the What's in your bag feature, you'd probably noticed that nearly everyone of the Verge crew chooses different generations of MacBook Air. Even after the Retina MacBook Pro, it seems that none of them are considering it at all.

I understand that the MacBook Air with Haswell offers crazy battery life (which is very important to writers), but this trend started way before it. I thought Retina MacBook Pro is pretty portable (always the major reason of choosing MBA as stated in the feature). Why is it still not popular at all..?