The map is built using strictly DHTML and Javascript (which, despite its name, has little to nothing to do with Java). So while I agree that it's good to have the newest JRE installed, it shouldn't be required to view the map -- it's designed so everything just works out-of-the-box. No plugins, no add-ins, no ActiveX controls, no downloads.
HNL will be there soon, as will the international feeds. Glad you like it!