Kevin J. Anderson is one of the more prolific, and controversial, writers of Expanded Universes, having worked on the Star Wars Expanded Universe, the Dune prequels, The X-Files and Starcraft among others. He has also written books for several universes of his own design, including The Saga of Seven Suns, the Gamearth Trilogy and Terra Incognita.
Kevin J. Anderson's works have stirred many controversies, most notably the Jedi Academy Trilogy, of which much has later been retconned by other writers. He also received a lot of flak, including on this very wiki, for his Dune prequels, which he co-wrote with Brian Herbert.
Expect to see a lot of entries on the YMMV section.