Tolkien was a genius, and he has earned my respect. However, he is a horrible writer.
One of the basic rules of any kind of storytelling is "Show, don't tell." And Tolkien simply does not understand this rule. He would have been better off writing an encyclopedia from the get-go: the story can never move forward for more than a few pages before it is interrupted for chapters at a time with anecdotes and history lessons. Tom Bombadil's house is one of the more prominent cases: two chapters (in a 20 chapter book, that's an entire tenth of the book) are spend in Bombadil's house. They sing, they talk about Middle Earth, Tom rattles off riddles... but the story grinds to a halt.
I just can't help but look to Frank Herbert's Dune, or Terry Goodkind's Sword of Truth series and see how they acquainted us with the culture and people of their worlds by inserting it into the story. It was all necessary, and it was all discovered throughout the course of the story. That is good writing. Tolkien's inability to develop the world without completely and constantly breaking the flow of the story makes the books unreadable for me. Amazing story, but poorly written.