This game was announced last week, but details about it were not known. Now, we know:

The World Ends With You: LIVE Remix, Square Enix’s winter-due GREE social title, is set in a world parallel to that of the original game. A new reaper named New Kid (Atarashi Koko) is introduced as a Navigator.

This New Kid person is probably the teased character from the iOS and Android "Solo Remix" version's secret ending:

Another TWEWY game! Wow, fantastic.

Awesome! Glad it's coming out on android as well. I hope it's less expensive than TWEWY on ios is, but I am pumped no matter what for more of this universe!!

@Hyuzen: I suppose I'd get it if I owned one of the devices it's coming out for, but I really want something significant for TWEWY and not all of these kind of "remixes". A parallel world seems like a flimsy premise, especially since they had already done that in the original game.

Without 2 screens it ain't TWEWY

I feel like this really isn't what people meant when they said they wanted more TWEWY games. I guess the social aspect wll make it a big seller in Japan though.
Just glad it's not a mobage game, good lord.

I'll be watching this, but can't say I'm too excited. On the one hand, I feel like TWEWY's ending was great and didn't really need a sequel so in that sense I'm fine that this is a social game I'll probably never play. On the other hand, if they're already giving us more TWEWY then I do wish they'd just give us a proper 3DS game.

Also, parallel world setting seems like a cop-out.

Some more information.

The new character Koko Atarashi actually isn't that girl teased from the ending but someone completely different:

And I'm having doubts that this game will come to North America.

Parallel world or not, I think it's messed up that this is starring Neku. He earned his happy life.