Government Information Preservation Working Group: Stability Study of Optical Discs

It's worth noting that in December the National Institute of Standards and Technology (NIST) posted a study on its web site on the stability of optical dics. The abstract notes:

This paper describes an initial stability study of commercially available recordable DVD and CD media using accelerated aging tests under conditions of increased temperature and humidity. The effect of prolonged exposure to direct light is also investigated and shown to have an effect on the error rates of the media. Initial results show that high quality optical media have very stable characteristics and may be suitable for long-term storage applications. However, results also indicate that significant differences exist in the stability of recordable optical media from different manufacturers.

The study can be downloaded from here.