USB broken on Canon 40D...

If the camera is still under warranty, make sure you send it to be fixed before the warranty runs out. When they fix this problem they will also clean and service your camera, so it's a good idea to get it fixed (under warranty). But there's no reason to worry about this affecting any other operation in your camera. I never use the cable to transfer photos - I always take the memory card out of the camera and transfer using a card reader.