The PlayStation Vita version of Persona 4 is "Persona 4 The Golden." So what's so Golden about it?
Famitsu lists the following (as summed up at Sokuho@Hokanko):
3G and Wi-Fi support
New event scenes
Added character outfits
New character Marie, voiced by Kana Hanazawa. She's a "mysterious girl" who appears before the main characters.
When you're about to die in a dungeon, you can send a message seeking help to other players. It's not specified how this system will work exactly.
Additional anime movie scenes, with new voices
1.5 times the voice of the PS2 original
New song for the opening movie
An element that has been highly requested by fans
In an interview with Famitsu, producer Katsura Hashino said that team Persona was originally looking into bringing Persona 4 to PSP. However, they wanted to retain as much as possible from the PS2 version, as opposed to some of the cuts they had to make for Persona 3 Portable. They deemed this impossible on the PSP. This is when they heard about the Vita, and determined that they could make something even better than the PS2 version.
Hashino promised that the Vita version will retain the qualities of the original while also adding many new elements.
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