what is the lifespan of the current optical storage media (cdr/dvd/etc.)?

Hi! Thanks for the question.

Optical Media storage will greatly depend on the materials used for
the manufacturing of the disc, the quality of manufacture, how good
was the recording, and the way it was stored.

Longevity of the following optical media according to manufacturers:

CD-R: 50 to 200 years (Recorded) 5 to 10 years (Unrecorded)
CD-RW: 20 to 100 years (recorded) 5 to 10 years (Unrecorded)
DVD-+R: 30 to 100 years
DVD-+RW:  30 years

Sources:

?Understanding CD-R and CD-RW?
http://www.osta.org/technology/cdqa13.htm 

?Understanding Recordable and Rewritable DVD?
http://www.osta.org/technology/dvdqa/dvdqa11.htm 


?On the basis of these types of experiments, manufacturers have
claimed that the lifespan of optical media ranges from 15 to 200
years. Generally, manufacturers cite longer life spans for recorded
versions versus unrecorded (i.e., blank) versions of particular
optical media formats, so order media as you need it and don't
stockpile inventories of unused media. Note that deterioration begins
at the time of manufacture, not recording.?

?Frequently Asked Questions About Optical Media?
http://www.archives.gov/records-mgmt/faqs/optical.html 


Longevity of other Optical Media types:

Hard Disks: 3 to 6 years
Magnetic Tapes: 10 to 20 years
Magnetic Discs (ex. Zip Drives): 1 to 5 years
Static Memory (ex. Thumb Drives): 50 to 100 years

?Tech Guide: Storage media lifespans?
http://www.zdnet.com.au/reviews/hardware/storage/0,39023427,20269043,00.htm 


Search terms used:
lifespan of optical media

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Easterangel-ga                 
Google Answers Researcher

Howdy saborg-ga,

To hopefully add to Easterangel-ga's great answer, it might not be the
lifespan of optical media that is the stumbling block in archiving data,
but rather having the device to retrieve the data 50 years from now.

The CD might still be good then, but if you don't have a working and
compatible CD reader, etc. then it is worthless.

Looking Forward, denco-ga - Google Answers Researcher

I think this is a very good and insightful comment. 

Thanks very much denco!