As typical 3D graphics performance grows, our need for better screen utilization will overwhelm the problems of effective 3D user-interface design. The new 3D user interfaces will use 2D presentation where it is appropriate, but it won't look like today's commercial GUIs. 3D really means 4D. Since true 3D display devices will probably not be commonly available in the near future, 3D will continue to mean for some time three dimensions projected onto the surface of a flat screen. In most cases static 3D images are hard to interpret. What will make 3D successful is the effective use of animation.
Unstructured information represents the biggest challenge to visualization.
Information that has a natural physical representation such as a map or real world object is not the problem. Years of work on geography and object modeling have inspired commercial packages to handle visualization representations of information that is tightly coupled to already recognizable forms. When information is readily quantifiable, computer graphing software is available to make all sorts of 2D and 3D graphs. Software is even reaching the marketplace for handling general hierarchical information. The unmet challenge is for visual representations of information that doesn't have a natural structure.