I'll update this for people like me who love FF.
Final Fantasy XV (yay!) has a much more modern feel to things. The levels they have been showing has cityscapes and it sounds like the story is going to revolve around a highly political agenda type story. Unlike FF 13 Lightning Returns where its more about the gods of the world dealing with each other and the fall out of a dead goddess, this game involves a country invading another to take a resource from them. With that the main character, Noctis, and his party have to do what you always do in FF. Start some sh!t up!
This game does have some third person shooter components that have been released and shown at a few events. I'm always questionable about these departures from the comfort of other FF games, but, I trust that they know what they are doing.
We know that Noctis is the prince (Japan loves to use the term prince but it's more accurate to say he's probably the son of...) of a mafia like family whose job is to protect the crystals of the world (the resource that invading country is after) and that we meet someone named Stella.
With all that said, there's still little known about this game but its probably going to be socks rocking!