I have been part of LOTRO since A2. The game has come a long way since then and has made many improvements. The world graphics are great but the biggest problem I have is the Character models and animations. They have to be the worst I have seen in quite sometime. If you really want to read up on it there is a few big threads on the subject at the main site.
I also have issues with the UI and mouse control and how sluggish it is. Again if you really want to read up on it you find many posts on these issues.
Other big issues in beta was the classes all being the same. A 35 Hunter is the same as any other 35 Hunter other then a few subtle differences with traits.
The world is to small. I can run from the Shire to Rivendell in about 35 min. The run from Buckleberry to Bree in less then 5 min. If you thought Wow was big then your going to be very disapointed.
Another issue is crafting is pretty much a grind for little reward. I found it to be pretty worthless for I always found quest items that were better before I could make a item of equal or better value.
The last issue that comes up is its a lot like wow. Well you will get many different answers on the forums. I myself have called it Wow light which I feel is not a bad thing but to many that is blasphemy. All I can say is give it a try its open beta right now.
I for one will not buy the game on release and will wait for most of Middle Earth to get filled in. I want to play in Middle Earth not a small part of it.
I hope by then they improve the Character models and animations which is my biggest issue.