The next version of zBrush is going to have box modeling tools.  That alone could be taken as evidence that sculpting hasn't replaced modeling.

Sculpting is great for organic shapes, complex contours, and for the way that you do not need to concern yourself as much with poly counts and topology until later.  But there are also many things that one would likely not sculpt.

Take a look at various programs galleries.  These are usually the best works produced by that software and they can show you not just what the program is strong at, but what it is weaker at.

In the zBrush and Sculptris galleries you'll see many portraits, body sculpts, and creatures.  But in the zBrush galleries are also numerous mechanical concepts, some of them very stylized and many quite complex.   If you were to look at a collection of images from SketchUp you'd see many more buildings, interiors and exteriors, mechanical components and designs but very characters or creatures.  What you see the most of usually represents the programs strongest features.  One of zBrush's strengths is the speed with which an experienced user can illustrate a concept.  Similarly SketchUp's is valued for the ease with which lets users model geometric forms quickly, cleanly and accurately.  And similarity in two models produced by those programs would belie the huge differences in those programs methods of working and tools provided.