Naughty Dog has explained that Trophies in Uncharted will be awarded for exactly the same things as medals already are.
These have been in the acclaimed action adventure game since launch. There are around 47 of them and they are dished out for getting lots of headshots or staying alive for a long time or using one weapon to kill hordes of baddies, for example.
The only new addition will be a Platinum Trophy given for collecting all the others, according to according to Naughty Dog speaker Arne Meyer on IGN.
To earn Trophies in Uncharted you need to start a brand new saved game. Meyer said retroactively rewarding you "would have been nice", but Uncharted allows save-files to be moved around and Naughty Dog thought some people might cheat the system.
There is still no specific date for the Trophy patch, although we're told this will arrive very soon. There is nothing else in the update.