Having never used dreamweaver or another program such as frontpage, how hard is it to update the sites? I have a couple of sites built the the CMS MDPro. On the weekend I will write a bunch of articles, then schedule them to post every 2 - 3 days.

Sites are as easy to update as the developer made them from the beginning. Sometimes WYSIWYG tools will work adequately. Sometimes they will fall on their faces. Sometimes CMSs will work adequately. Sometimes they will greatly restrict what you can do and will require your site to be served up using second-rate markup.

It all depends on the individual site :)