Danish usability consultant Jakob Nielsen earned his unofficial title of "Web usability guru" as an early promoter of standardized Web design. You can thank him, in part, for blue links. He prompted a lasting, vocal debate by distinguishing between print and online approaches to eye appeal, readability and writing style. (For example, see "History of print standards.")
Unafraid of controversy, he continues to tout astonishing concepts such as "Why you only need to test with five users" and is known for his strong--some would say "extreme"--opinions on minimalism and uniformity.