Initial testing of the first CDs gave them a life expectancy of only 5-10 years maximum. Today, manufacturers are creating CDs, that according
to estimates, will last between 30 to 100 years, or as long as 300 years depending on the type of disk.
Longevity depends on a few factors–proper storage conditions, careful handling, and limited exposure to light. In addition, the dyes used in the manufacture of the disks can affect their longevity.
The larger issue with CD/DVD technology is the retrieval of the material written on them. Again, the question is whether the equipment will be around to allow you to look at the files in five, ten, or twenty years. Even if the material lasts to the outside date of 300 years, will anyone really be able to look at your photo disks?
Libraries and archives are very concerned about digital preservation. The Library of Congress has an informational page (www.digitalpreservation.gov/you/digitalmemories.html) which describes saving everything from email to digital photos.
If you have these same concerns, Preserving Your Family Photographs goes over steps for planning for obsolescence. I also talk about proper storage, handling and labeling of CDs and DVDs to minimize the risk of losing your precious photos.