This may be a dumb question, but are you rendering the scene? Reflections only show up in the final render, you won't see it in the working screen. If the reflection doesn't show up in the render, make sure ray tracing is checked in the render options. Also make sure the camera angle is correct so you can actually see the reflection, maybe it is reflecting but you are just not seeing it. It does work and works quite nicely. I have made all sorts of reflective objects, including people to get that metallic look like in the Sexy Robot series of drawings.