Looks to be a large rail shooter. It does not appear to be a sandbox game.
I'm sure the engine will kill and the graphics will be great. I kinda doubt the game it's self will be wonderful.
We have had very some good games since id produced Doom3 and Quake4, well id and Raven. Those games although fun were not at the level of Stalker or even Fallout 3 and NV in openness and involvement in the world.
A real sandbox allows many different ways of approaching a problem. For instance; my favorite weapon in NV is a big horn sheep. I don't think the developers intended this.

In a Stalker game you can do it any way you want. Some ways will make the endings a bit lame but that's because you missed important points. I doubt that will be possible in Rage. You will have to complete each section before advancing to the next. A rail shooter.