1UP- Persona 4 Golden probably didn't have to be much more than a port. Fix the aspect ratio, give it a high-definition makeover, and the portability would pretty much sell itself. But this is Atlus we're talking about, and they've used this opportunity to push themselves even further ahead of the game on RPG design.
As I've discussed elsewhere, one of Persona 4 Golden's most intriguing new features is its network functionality. In essence, it's possible to see what other players opted to do on a given day, and use that as a roadmap in your own decision-making process. In that, it's a bit like the messages in Dark Souls; or perhaps the ominous bloodstains that offer a warning of untimely death ahead.