Number 1 criteria, does it work with our revision control! For the php stuff, eclipse. For the portal the eclipse based ide that comes with the portal. For the real-time 3d stuff, it's all written by the server software on the fly. Because there is no set layout of what the resulting page will look like the layout of the page is created in our display builder which then gets rendered by the display engine into either a 2d display by Java or a 3d display by JavaScript, and the JavaScript is written by the java server-side.
The java is all written in Eclipse.