The article discusses the realism Euphoria has added to the game, how vehicle handling has changed and the new combat system. It also describes a couple of the missions they got to play, which you may have already read. If the hands-on is not something you want to read again, then they also have a nice retrospective article on the GTA series which is something you might be interested in.
Unlike previous GTA heroes, Niko feels and moves like a real human being. He doesn't control like a remote control car, stopping and starting on a dime. He's got momentum, he's got force, so running down the streets or ducking behind cover from gunfire feels more realistic than ever. And he's not the only one.
The cars in GTA have also gotten a revamp on the control front. It definitely takes some getting used to, but the cars in GTA don't all have infinitely small turning radii or racing suspension. Some are real clunkers, while others zoom along at a nice clip. Cop cars, for example, pick up speed nicely and are able ram with the best of them, whereas an ice cream truck has a little less piss and vinegar.