I was enthralled by a recent series on Sacnoth's Scriptorium, which offers an authoritative and quite readable treatment of D&D's relationship to the Tolkien estate. And Mr. Sacnoth is certainly in a position to know the gory details (his personal role in things starts in part 3), and he pulls no punches in his account of "Who Killed the Middle Earth RPG?".
JRR and D&D, Part 1
If you have any interest in the subject, I recommend it. If only Sacnoth would scan and post that mockup Tolkien RPG cover art!