Lighter is better for me, as I carry my laptop all the time. The laptop I had before my Mac was really heavy, bulky, caused back pain and limited what else I could carry. Lighter the better please.
I'd bet that things like having or not having a car dictate a lot of our everyday carry choices - it has for me. Now I'm wondering if an iPad Mini is too small...
Of course, one is sometimes a proxy for the other, but it's not a given.
I also travel a lot, and want a thin, lightweight laptop - but it must be functional, reliable and have excellent battery life; I don't care a jot if the next generation is 1mm thinner than the last if it means sacrificing keyboard usability and reliability, battery life and cooling.
We past the point where thinness was an issue a long time ago. Now it's just a pissing contest.