The game ambience owes more perhaps to Petr Jackson than to Tolkien and it is unusually violent (albeit the spouting blood is all Orcish black). Nevertheless I am enjoying it greatly.
I have seen this style of game called "Ubisoft like Open World" similar to the recent Assassin's Creed and Far Cry games. You have a beautiful open world to explore with many optional side-quests and mini games in addition to a main quest line. I have also seen criticism of the repetitiveness of it all.
Shadow of Mordor does have many repetitive elements and yet it offers a large range of different game play opportunities. When you are first thrust into the world the vast array of things to do is quite over-whelming. You gradually learn how it all works by simply playing. There is never only one thing to do next and the game is very happy to let you develop your skills at your own pace. It is true that once you master one aspect of the game you will find that it crops up over and over again and yet I find a certain satisfaction in that. To be honest I am enjoying the game more now than my first few hesitating days when any given enemy could kill me. Indeed several lowly grunts managed to feed of my repeated demises to grow into powerful adversaries. Now I find I have slipped into a groove and it gives me quite a bit of satisfaction to slaughter these uppity Captains who boast of killing me in the past.