You may yourself have noticed the problem of bleed-through
on cassette tapes that are left un-played for years.
With time, the tapes become entirely unusable.
CD-ROMs are potentially better, but subject to their own problems.
They can be rendered unreadable by simple scratches.
Moreover, as the Newsweek
article notes, "Even
the CD-ROM, once touted as indestructible, is proving vulnerable
to stray magnetic fields, oxidation, humidity and material
decay." High quality CDs may last as long as 50 years,
with care, while the cheaper ones may be useless in 5 years.
The important thing to remember in all of this is that everything
has its appropriate purpose. Electronic media are great
as formats for access. But they are not the best format
for preservation. Your Session records or other
precious documents are still best preserved on acid-free paper
or even microfilm. Each of these media can be expected
to last up to 400 years, if properly stored. Our
advice: Backup your files-- and print the important
Resource reading on this subject, can be found at www.safesupplies.com