I wouldn't expect that, given how the first game was completely linear and went through chapters.

If we will be able to explore anyway though then that's a whole new twist to the series. (Just like how they added a mini-gun. I still can't get over that!)

I enjoyed Metro 2033 very much. I am currently reading the english version of the book and it's awesome. I can't wait for this one to come out.

By explore I just mean will the fiction explore what things are like outside more. Not literally exploring, lol I should make that more apparant as this is a video game so exploration has a totally different meaning to what I'm saying there :p

There will be more time spent on the surface than the first game, but the surface is still a highly radioactive wasteland.

RPS: What about environmental hazards and so forth? Any variation there?

Beynon: The world of Metro is a hostile place, full of environmental hazards and foes, both humans and mutant. The surface is the most hostile environment of all – it’s full of things actively trying to kill you, and that constant struggle for survival, the desperate need to preserve your lifelines of ammo, medical supplies, light and filters is something we feel is intrinsic to the Metro experience. One of the things we were proud of in Metro 2033 was the sheer amount of environmental variety we achieved for a ‘post-apocalyptic’ game. We used light in particular to give us a rich colour palette, and we’ve tried hard in Last Light to keep surprising the player with a scope and scale of the environments they’ll encounter. So yeah – plenty of variety. And most of it deadly.

RPS: We’ve seen quite a lot of “surface” shots so far, is that indicative that we’re going to spend more time above ground?

Beynon: We take the player back up to the surface multiple times in Metro: Last Light. I think on balance it will be a little more than it was in 2033.

http://www.rockpapershotgun.com/2011/11/15/casting-light-on-metro-last-light/