Basically what Facebook, Twitter et al look like. But that as a Magazine type theme.
I like the grey lines that give clearly divided spaces and makes good use of small spaces. I do not like stuff like this: http://totaltheme.wpengine.com/boost/
wasting space and give no clarity.
My all time favourite WP theme is Newspaper by TagDiv and I use it for all kinds of use cases. But even it lacks the above clarity.