Compact discs are by their very nature designed to last a long time.
The inner layer is aluminum and the outside is a durable plastic, both of which will sit in a landfill for a very long time indeed. I suspect there isn't enough aluminum in them to justify recycling. A few years ago there was a debate about the biodegradability of the CD's jewel cases, and some record companies switched to using cardboard slipcases, but I feel the discs themselves are more of a problem.