MMORPGs are great if you're willing to go the whole hog, play for several hours a time several times a week and forego pretty much all other gaming and entertainment to keep the habit going.
You do have to put the effort in and get involved in a good guild with plenty of other players your level that you get on with in order to make the most of it though. I played WoW for a couple of months and would highly recommend it unless, like me, you don't have the time or dedication to put in.