I've seen this on more and more sites as the internet grew, and the reason why was easy. Too many complaints about dates and times not being right due to... Time zones. When it's 6 p.m. in the east side of the U.S. in my own time zone it's either mid-night or close to that, and there are even places at the world were the time difference is more than 24 hours. In order to cover that all up more and more sites began to replace their exact date and time system with 5 seconds ago to 3 years ago... After all if I posted a meme 5 minutes ago, then no matter if you are in Amsterdam, New York or Sidney, 5 minutes is then still accurate.