Are there any changes in NSF proposals/awards processes that are likely to be of special interest/relevance to PIs?
At the top of a recent NSF Solicitation the following note exists:


  A revised version of the NSF Proposal &amp; Award Policies &amp; Procedures
  Guide (PAPPG), NSF 13-1, was issued on October 4, 2012 and is
  effective for proposals submitted, or due, on or after January 14,
  2013.
  
  Please be aware that significant changes have been made to the PAPPG
  to implement revised merit review criteria based on the National
  Science Board (NSB) report, National Science Foundation's Merit Review
  Criteria: Review and Revisions. While the two merit review criteria
  remain unchanged (Intellectual Merit and Broader Impacts), guidance
  has been provided to clarify and improve the function of the criteria.
  Changes will affect the project summary and project description
  sections of proposals. Annual and final reports also will be affected.
  
  A by-chapter summary of this and other significant changes is provided
  at the beginning of both the Grant Proposal Guide and the Award &amp;
  Administration Guide.


By my reading of the section in the PDF that lists the changes, the following might be of interest to PIs:


  Chapter II.C.2.f(i)(c), Biographical Sketch(es), has been revised to rename the “Publications” section to “Products” and amend terminology and instructions accordingly. This change makes clear that products may include, but are not limited to, publications, data sets, software, patents, and copyrights. 


Plus, a minor change to the Indirect Costs section w.r.t. international participants, a minor change in the Facilities, Equipment and Other Resources listing, 

A change in the definition of "New Awardee":


  Chapter II, Introduction, has been modified regarding the period of time after which an organization is considered a “new awardee”. Organizations that have not had an active NSF award within the last five years (formerly two years) should be prepared to submit basic organization and management information and certifications.


Prior funding:


  Chapter II.C.2.d, Project Description, has been revised to clarify that, in the Results from Prior NSF Support section, “prior” NSF support includes current NSF funding. This section also was updated to indicate that information should be included irrespective of whether or not the support was directly related to the proposal, or whether or not salary support was provided.


References Cited:


  Chapter II.C.2.e, References Cited, has been updated to specify that if there are no references cited, a statement to that effect should be included in this section of the proposal and uploaded into FastLane.


And various other minor changes...