I often come to HN for the discussions, not for the links themselves, and unfortunately that's something missing in "New". It happens quite often that the submission itself is not terribly interesting (e.g. a blog post ranting about some database engine), but nonetheless it spawns a fascinating discussion, filled with first-hand anecdotes and other insights.

So when I browser "New" I usually upvote submissions that have potential to create an interesting discussion (so I upvote what I believe _other_ people will find interesting, in a Keynesian beauty contest way).