For starters, I've been in exactly the same situation- having to render shiny, metal objects and have learned that it is not easy, especially if you have to fold them them into visually interesting marketing content. You may want to read up on the following threads.
- Rendering shiny aluminum and creating custom environments
- Putting machined finishes on metal surfaces
- When jewelry gets "too" realistic
- Customizing your own Bump Maps
- A primer on customizing backplates
- The pitfalls of the corner radius
- Watch out for high resolution
Before you get too deep into visualize, however, make sure you have usable hardware....or you'll lose your mind manipulating and waiting for your renders. Lastly, you'll want to cruise the game developer forums for some solid rendering advice.