Update: Fixed in a new release of the Exporter. A working version of the scene is here.
Fails in Firefox 3.0.12 and 3.5.2. Website reported as a failed site.
Using Max 2009 on Vista x86, SP1, I created and exported a simple scene with a knot, 3 lights and a camera.
Here is the scene on this website.
The model does not play in Firefox 3.0.13, either from the file system or from this website.
It does play in MS IE 8 both from the file system or from the website.
The samples on the hypercosm website play in both MSIE 8 and Firefox 3.