Oh, no, I don't mean it like that. The open world is always there and it's all seamless (or at least, I believe the game is split up in big regions, but each region is like a level, a part of the game you have to pass). So you can always roam around, fight random orcs and wild life, maybe collect some things.
But if the Nemesis system was removed from the game as it stands right now, there would hardly be any game, just a hollow open world. From what I gather, most of the content comes from you trying to 'take over' the five leading orcs of your currect region, and you can decide yourself how you fill in the 'take over'-part. You can't just run up to the leaders and kill them, you have to gather intel on them to find out who they are, then go through the ranks and work up to their lieutenants and use them to get to the leaders. You can dominate one orc and try to level him up by throwing challenges at him, then have him take on the leader, or just dominate him to directly attack the leader and use this disruption, or send him to the leader as a warning, making the leader stronger (which I believe increases the chance for better equipment or runes).
There's tons of possibilities, and the Nemesis system creates missions; a rivalry between two orcs means they will duke it out and you can be there to partake in it. There's always a reason to travel around and do things... but most of it comes from the Nemesis system, from what I gather. And I think that's cool, kind of a new approach to things, I like futzting around with 'power struggles', like in the 'The Godfather 2 game' (even though I know that's not exactly a technical marvel). I'll certainly do the review if we get a PC copy, otherwise I'm getting the game anyway.
I also really dislike LOTR. Like, a lot.
