Here lately it seems like Google has been loving fresh content. I usually try to post at least once a week, and sometimes, if it's a new topic (something trending on twitter or breaking news), my pages can get on the first or second page within a day or two. Small surges of traffic. Haven't really seen a correlation with larger KWs, but then again there are so many factors.
Just curious, but how often do you update your site or blog? Do you see boosts in traffic when you do?