I wonder if it is possible to use the macro option (#+MACRO:) to save the typing
  of header options (of code blocks).   For example, currently it does NOT work if I try to use 



#+MACRO: p  :file $1.png :width 1000 :height 800




  to shorten the header of a code block to



#+begin_src R {{{p(plot)}}}
Anyway,  I found Org-Babel Mode to be a great tool since Sweave for writing R literate program document.   I wrote a how-to article on its use (see attached file "how-to-use-*.html", other files are raw and support files).  Hopefully it can be useful to some users.  

Sincerely, 

Feiming Chen