Off-topic: I can't say how LOTRO is due to the NDA. However, I will reiterate what is general knowledge so far:
The game engine is an upgraded version of the engine used to run DDO. So, chances are if you liked the gameplay of DDO, you'll probably like the gameplay of LOTRO.
There are no true casters. This makes sense in Tolkien's world, as there were only a handful of wizards (Gandalf and Saruman being the most prominent). They have implemented ranged non-bow attacks in an interesting way though, which I'll be able to tell you more about as release gets closer.
Also, the game is based on the books, not the movies (thank God). So, whereas you don't see Tom Bombadil in the movies, expect to see him in the game, etc.