3D on the web – What does that mean to you?

3D is one of the buzz words in IT. Everyone seems to be doing something with it. But how are you using 3D on the web? And what kind of 3D? Fake 3D as in images with a suggestion of depth, rotating menu’s, or real virtual worlds like Second Life, where one can walk around freely?
Is there even a place for such content? What kind of content is likely to be put in virtual worlds on the web? Are clients asking for 3D? What kind of technology seems to be getting the upperhand: Flash, VRML, X3D, …?
What are the problems with it and how would you like to see the 3D (r)evolution on the web?