Some very interesting thoughts related to 2.5-d and 3-d information related to experiential computing and abstraction are presented in an article by Fred Limp.
This article clearly shows that 2.5-d though often confused with 3-d is not 3-d. In addition to good exposition of technology, this article has many very interesting ‘GEMS’. Some are mentioned here:
Why is adding 3-D so â€œcool?â€? This has a lot to do with scale, which has a lot to do with abstraction, and abstraction has a lot to do with experience and understanding.
For a business, less abstraction means a larger market.
Some argue that a lack of real, human-level detail in many community-planning maps are a root cause for many bad planning decisions, because decision makers are working with abstractions that donâ€™t represent the situationâ€™s reality. Wouldnâ€™t it be ironic if maps were the source of many problems, rather than the basis for their solution?
Many of the technology drivers were initially developed in isolation, but people are increasingly seeing the value in integration.
This is a good read even if you are not interested in GeoSpatial information systems, you may find this article interesting.