${PN}, ${SLOT}, ${PV} and installational directory also need to be discussed.

I suggest:
  - PyPy 2.1 implementing Python 2.7:
      PN="pypy"
      PV="2.1-r200"
      SLOT="2.1-2"
      Symlink of interpreter: /usr/bin/pypy2-2.1  or  /usr/bin/pypy2.1-2
      Installational directory: /usr/$(get_libdir)/pypy2.1-2

  - PyPy 2.1 implementing Python 3.2:
      PN="pypy"
      PV="2.1-r300"
      SLOT="2.1-3"
      Symlink of interpreter: /usr/bin/pypy3-2.1  or  /usr/bin/pypy2.1-3
      Installational directory: /usr/$(get_libdir)/pypy2.1-3

--
Arfrever Frehtes Taifersar Arahesis