Cisco for dummies?

Actually, to cover everything the various flavors of IOS does, you would
probably need different nutshell books targeted at different audiences,
perhaps one for each flavor of IOS. (Enterprise, IBM, Desktop, ISP...) I
don't think too many people on this list would care about the SNA $%#^ that
Cisco-Blue does.

Its easy enough to put a note at the beginning of each section or
perhaps some kind of icon that refferences which release a given
feature is in.