a number of post ask where in RFC 3978 the right for 3rd parties 
to reproduce RFCs is noted

it does look like some of the clarity of that right got lost
in the effort to reduce the copyright notice that needed to be
carried on all RFCs but the rights to let RFCs be "freely reproduced"
(and translated) and for MIBs to be extracted are specifically noted 
in section 7.1 

note that the removal of the "distribution of this memo is
unlimited" notice on RFCs was not discussed or directed by the process
that produced RFC 3978 (as far as I can recall) - and I do not know
why its no longer being used  - (the RFC Editor may quickly refresh my
memory  )

in case anyone wonders, RFC 3978 was not intended to remove any
rights for 3rd parties relating to IETF RFCs - instead it was
intended to make some of the rights (extracting MIBs for example)
even clearer - this discussion indicates that the desired level of clarity 
was not realized in some cases.

teh new ID is intended to add additional rights for everyone (inside or
outside of the standards process) to extract text other than "logical
parts" like MIBs - it is also intended to give the IETF the ability to
grant 3rd parties the right to make derivative works outside of
teh IETF standards process - note that, if the latter right is
established, at some point in the future the IETF could decide that
"open source standards" are a fine idea and set up some mechanism
to enable them - thus the suggestion was made (by Sam as I recall) at
the last IPR meeting to at least get those rights in hand without
having to resolve the open source standards issue first. - I suppose
that the text in the ID could be changed to permit the IETF to set up
a process other than case-by-case for granting the derivative works
right - opinions?

7.1.  Rights Granted in IETF Contributions

   The IETF/ISOC must obtain the right to publish an IETF Contribution
   as an RFC or an Internet-Draft from the Contributors.

   A primary objective of this policy is to obtain from the document
   authors only the non-exclusive rights that are needed to develop and
   publish IETF Documents and to use the IETF Contributions in the IETF
   Standards Process while leaving all other rights with the authors.

   The non-exclusive rights that the IETF needs are:

   a. the right to publish the document
   b. the right to let the document be freely reproduced in the formats
      that the IETF publishes it in
   c. the right to let third parties translate it into languages other
      than English
   d. except where explicitly excluded (see Section 5.2), the right to
      make derivative works within the IETF process.
   e. the right to let third parties extract some logical parts, for
      example MIB modules