Hi
You can also use GL4Java which makes an extension throug JNI So you can use simple OpnenGL-Code for displaying youf 3D-Data. It is available under http://www.jausoft.com
It is really great and a lot of Java-Apps were done with this thingy.
However, you have to install it, so you cannot use it on a browser where this one is not available. But the same it is on Java3D, which is JDK 2.0 which is not implemented the common Browsers JVM