To address this with our clientele, I usually refer to some of the research and writing on games for learning, including works by Gee, Squire, Johnson, Beck and Wade (who published the provocative book Got Game.) [Hopefully now he'll also refer to Kapp, O'Driscoll and Gadgets, Games and Gizmos for Learning.] I find that if I can help the decision-makers make the positive connection between good game design – the reason people become so hooked on the experience – and memory creation and retention, I can then move on to making a connection to serious gaming. First step; use good game design for serious learning outcomes.
Secondly, I often draw the analogy that an immersive 3D experience for serious learning is not really different than creating in-class role plays or doing other immersive experiences (such as outdoor team-building events). This helps make the connection that it is not about the game or the technology, it is really about designing an experience to get to relevant learning outcomes.
Finally, there is sometimes an objection related to perceptions of expense – that the 3D solution will be cost-prohibitive. The good news here is that the cost of technologies is coming down as the capabilities of standard hardware and networks in corporate environments has come up, lowering the technical and financial barriers to entry.
Links to books mentioned above:
Catalog of Recommended Books, Games and Gadgets Recommended Games and Gadgets Recommended Books Content Guide