[XLcommerce]

A few people have mentioned information density as being important. I've got the 'Stylish' chrome extension installed with a userstyle for hn which looks like this:

table > tbody > tr:nth-child(3) > td{-webkit-column-count: 2; }

2 column layout is v.cool. Makes the front page as well as the comments section much more readable for me.

example: http://imgur.com/a/oidEM#1

[dhx]

It is easier for a user to scroll down a long continuous list than to hop back and forth between two columns. This is particularly true for ordered lists (as is the case with HN).

The only thing I strongly dislike about HN's current design is that comment line lengths are far too long[1].

[1] http://baymard.com/blog/line-length-readability

[XLcommerce]

It reads like a newspaper. You read one column at a time. No hopping between columns.