Call of Juarez: The Cartel, is a departure from the norm for the series. The two previous games were originally westerns. Now it's a pseudo-military shooter based in the modern day Mexican drug war. The one guy has a cowboy hat, so you can see that the game is kind of sticking to its roots, if its roots include Uzi's, AK-47's and a crap ton of F-Bombs. It the video you can see three characters working together, challenges, a revive mechanic, and a progression system.
As to the authenticity of this trailer, all I can say is this: I once made a wrong turn in El Paso. I spent a good 45 minutes in Juarez, and I'm gonna have to say that they nailed it. It's exactly how I remember. The only thing that's missing are the dozenss of children running up to the car and trying to sell gum.
Call of Duty: Desert Drug Bust Call of Juarez: The Cartel will be available on the Xbox 360 and PlayStation 3 on July 19th. It supports 3 player online co-op.