I was into VRML (Virtual Reality Modeling Language) in a big way about 8 years ago...which means I was WAY too early for that party.

It whithered on the vine back then for at least a couple of reasons: online business never really took an interest in it (which sadly meant that VRML and money were never close friends), and most consumer-level computers weren't powerful enough to make VR a compelling experience. Authoring tools were scarce, crude and expensive. I wrote it by hand--it wasn't particularly difficult, though a background in linear algebra certainly helped.

It seems that 3D may still be slowly be edging it's way to the forefront. MS Vista has some interesting 3D interface capabilities. I've also seen some attractive e-commerce sites using it in a modest way, and the hardware may finally be catching up with the dream. Ultimately, it'll be up to the users. If it adds enough to their experience, it may still catch on.