If you want something that is less popular science (the book was after all written for a popular audience), check out his papers.
Yes, his beard probably gets more ink than anything else. That's sad in a way (don't judge a book by its cover), but it's probably also good in another way, since it makes him pretty unforgettable.
I have read some of his papers. I should have been more clear: I like him a lot.
And I do agree with you that it makes him unforgettable. I personally think it is done with deliberation. To a certain degree, he is going to be treated as a quack. He even says so often. By dressing the part of Gandalf the Gray he's almost openly mocking them.