Great fast-paced team combat, character roles well defined plus big combinations of powerful skills and a huge arsenal.
It is a really underrated game, It's difficulty is not "wii casual" but it isn't "darksouls" hardcore either, but it's a game that calls for a bit of thinking in terms of gameplay, for the strategy that is required in combat. The gameplay is well built, it's a fast-paced team combat with characters whose class roles really work. It has a lot of options of equipment and skills that if you can manage you can build very powerful heroes.
The best feature of the game is how you have to play as a team to progress through the levels, which makes the multiplayer really fun. Each character has it's own role, strengths and weaknesses. Every time you play a different character you have to adapt your strategy and gameplay, because you should not jump in the middle of a group of raging Orcs with a "fragile-oh-don't-touch-me-i'm-a-healer" Elven Loremaster and attack them from far with a "god-damn-hard-as-stone" Dwarf Champion, while the "leader-stereotype-fast-striking" Dúnedain Ranger keeps looting the corpses... But even though your hero has already a base defined, it is up to you to build his skills with a big number of combinations. What this game really says is "DON'T BE STUPID", think about your combat role, help your friends and share the loot - which is very rewarding.
Concerning the game story-line, it's not that really strong but it's fun. It has that cliché element that most role-playing games have, but we're talking about Tolkien's universe, it IS the basis from where all medieval-fantasy elements come from. If you're not acquainted with The Lord of The Rings trilogy, it might be a little strange/dull plot, but it gets really interesting when you have read the books, or watched the movies. In my vision this is a more fan-centered game, but still, a really good game - the best of the LotR franchise - that kept me hours straight playing.
Although it has a few flaws, as not having the option to save your progress in-game and not being able to switch characters while playing a mission, these are not THAT impairing, but to me the most frustrating thing about it was how short the game is, it could have a few more side quests, more maps, etc. It also fell short of NPC's I think. The good thing is that after you finish the campaign - which is set to Normal Mode by default -, you can keep your character with it's current level and equipment and start over in Heroic Mode and then play in Legendary Mode - but you might get sick of fighting the same monsters over and over. You also have Challenge Maps where you have to defeat waves after waves of enemies. I actually have begun playing the Heroic Mode right after completing the Normal Campaign because I was really into it.
ANYWAY - it's always great to destroy and mutilate hordes of rampaging Orcs and Goblins and that share amount of Trolls, loot and pile caves and enemy outposts followed by great graphics, from very good character models to beautiful landscapes. I do not regret playing it, it was in fact, a really interesting journey through the world of LotR that made me want to read all the other book such as The Hobbit and The Children of Húrin.
Play It. Enjoy it.