After I watched the trailer more Grand Theft Auto V, we came to some conclusions. Not to extend and reach to the point.
The trailer begins with "Why did I Moved here? I guess it WAS the weather", says it would be a good man at least once. So from this we conclude that the protagonist had a dirty past. And then at 0:39 0:46 and 0:50 that there is a older man who seems to be Tommy from Grand Theft Auto Vice Verceti City, and the beginning trailer words could say that Tommy Verceti moved from Vice City in a city with roughly the same climate that is Los Angeles. So assume we have a main character. Now to talk about cities. And the next game in the series is called Los Santos Los Angeles, we see this very clearly in 0:53 where the front wall says "Los Santos", so we have Los Santos but ... there will be other cities? Of course. At 0:27 we see a kind of ... desert, could be the turn of Los Santos and Las Venturas (Las Vegas) or ... San Fierro (San Francisco) So, we conclude that the action will happen not only in Los Santos. Other interesting stuff ... at first we see a dog sitting next to two people on the beach ... so Rockstar Games has finally put the game animals. Besides dogs and birds have this time are not just moving textures that disappear ... do not know where when you shoot (If you do not know speak for San Andreas). See you in convertible car trailer 0:23, 0:19 skyjet from the mountains at 0:20 which I have called Chilliad (San Andreas again). And ... that's all I managed to make out. If you find something you also please let us know via comment. See ya!