Johns Hopkins University's online education program website, which deals with technical topics that are required to teach and support an online class, has Nvu on the top of its list of recommended HTML editors. Nvu is the only FREE WYSIWYG HTML editor listed on their web page. They recommend it even to non-technical users! Macromedia Dreamweaver, M$ Fronptage and M$ Word are also listed with their major drawbacks of steep learning curve, IE-centric features, and limited features respectively.
They also have a brief and to the point introduction to Nvu as well.