To scroll down a list of "News for nerds; stuff that matters". That has been the beauty of /.: its simplicity in presenting many stories I can scroll quickly through when I have the odd moment to check while at work. It is always open in a tab when I'm online.
I used to visit Ars and /. about equally. I still read Ars, but I no longer keep it open in a tab as their new design makes the 'quick scan' impossible. I've relied on /. as an aggregator of headlines from all my favorite tech/science sites (including Ars). The new design takes away the clean, concise way of presenting so much information so well.
Why fix what ain't broken? The new design is horrible. Please don't. Please.