I had this same discussion on another HN thread a while back. I prefer lines to run as long as possible; I find it difficult/distracting to move my eyes to the beginning of the next line every few seconds. I'm sure I'm in the minority, but I have to believe I'm not the only one out there who feels this way.

Rather than having the website author wrap lines at a width that works for the average user or use case (which may only be optimum for a percentage of users or use cases, which may not include me), the user can simply make their browser whatever width they prefer the lines to wrap at. This way, everybody gets to choose what works for them.