With recent content, I prefer to know how many hours/days ago it was posted. I find that exponentially more helpful than guessing timezones and things like tha

With recent content, I prefer to know how many hours/days ago it was posted. I find that exponentially more helpful than guessing timezones and things like that. However, you're completely right when it comes to timestamps exceeding a certain age. That's why in my own projects I use a mixed approach: display recently changed things in relative time and all others in absolute terms. I also advocate to display more detailed information when the user mouses over a timestamp, just so the data is there if needed - as it is in this case.