This is a bit tangential: Every start-up that YC funds is potentially worth an essay. Isn't that why they are funded? They solve a problem that nags many. So I am not surprised to see Rescue Time linked in there (The title itself is a sure bet that it would).

However, given the wide reach of pg's articles (beyond news.YC), should the link merit a disclosure? There's a fuzzy notion of when that needs to be done and I am intrigued by what these notions are. People would be baying for Michael Arrington's blood if he was found responsible for such an omission, but I am guessing it is a non-issue here. So what's the difference? A higher implicit trust-ranking for pg? An assumption that everyone already knows about the linkages between YC and RescueTime? Or the fact that these essays aren't actively promoted by pg. That could be a factor even if the probability of his latest essay being posted within hours, here or elsewhere, is now close to one.