Linking: How clearly differentiated do they need to be?

Have we finally passed the Jakob Nielsen threshold when it comes to linking? We now see sites, such as CNN, designed for the most basic of users presenting numerous different navigation models.

For example today’s edition of CNN uses several different models, few of them explicit. The top navigation assumes users know that they are links. The graphics link to the story, as do the titles below them. It is assumed that the user knows to click on them. Underneath the titles is a description of the article followed by the words FULL STORY. Although FULL STORY has a slightly different color the link differentiation is remarkably subdued. Below the lead articles are a list of articles under the label "Latest News." As with FULL STORY the visual differentiation is limited to a slight color variation.

My only quibble with the usability aspects of this page is that the description text should also link to the article.

Nonetheless we are crossing a major threshold here. Average users are expected to assume that links exist without any visual clues. Will there still be users who go to this site and be confused as what to do next? Yes but people who are confused will soon be crossing into Crocodile Dundee territory. After all EVERYONE knows what escalators and elevators do.