Dune is perhaps the most seminal work of science fiction, to that genre what Lord of the Rings is to fantasy. It was also one of the series that inspired me to become a writer.
I discovered the original novels by Frank Herbert while still in high-school and loved them beyond words. The care and skill in building the universe, the depth and diversity in the characters, the sheer power in the story, was just mind-blowing. Herbert more than justly deserves accolades as one of the greatest of the greats.
And it is science-fiction at its core, using an imagined future to look very hard at very real issues. Much has been written about some of the social issues addressed in these books, and one can't read them without feeling driven to think about how they view the world they live in.
I was a bit leery when I saw that his son Brian Herbert and Kevin J. Anderson would be continuing the series after Frank's death, and so avoided the newer stuff for the longest time. When I went back to reread all the original books, I found myself curious, and wanting to explore more of the world, so I tried the initial prequels.
Needless to say, I've read them all, and now eagerly wait for each new edition. I'd like to think Frank Herbert would be quite proud. The books by these two authors do a great job of building on the world, continuing the feel, flavor and spirit of the original novels, and yet manage to show us history and elements we've not seen before.
Absolutely highly recommended, and probably the best continuations of classic series without the original author's involvement that I've ever read.