I prefer Achievements, mainly because I have a 360 and am more familiar with them. With the quick ability to compare games with folks it is very easy to see if someone is skilled or not in any one particular game. If, as I understand it, you get a platinum on ps3 for completing a game, I would argue that getting your platinum count up would be just as easy as getting an artificial gamerscore up.. beating super easy games (like king kong or CSI) gives you an easy 1000 gamer score, or an easy platinum trophy (yes?). So I don't see a high platinum trophy count as something I'd need to gravitate toward, particularly because you can easily view each game that a friend has "closed out" (gained all possible achievements for), and that is a very strong indicator of their abilities.
That said, if achievements were never around and it was a trophy system all the way around, I am quite sure I wouldn't lose any sleep over it. It is fun. It is a way to measure gamer-fortitude. It can shape the way you play (or don't play) some games. In the end, they are great tools to make us all tools!
