While CAD has been criticized as distracting from design, BIM offers the potential of dramatically increasing the quality of design. Design is much more than a "pretty building", which is certainly one goal of design. Good design also includes designing to the budget, insuring energy efficiency, consideration of maintenance and renovation costs, analyzing structural options and much more. BIM will bring real time "what ifs" and analysis to the design process.
We have designed, documented and built our buildings essentially the same way for hundreds of years, no matter if it was drawn by hand or in CAD. BIM offers the very real potential to completely change the process, the form of documentation, responsibilities, liabilities and the amount of money.