I generally go for what I think "deserves" an upvote. Where I keep figuring out new criteria for that, as I move around the site.
- I do consider if it could go viral, but In general, I suck at finding such content, so I tend to not base my vote on that at all. Since, Ivoting power falls, with every vote, regenerating a bit over time.
Circlejerking, is not what I really want to do though. I want originaility, so have I seen it before, I'll steer clear. (Though, if it's formulated in a better way, I might support it.)