As a meta rule setting up issues in the tracker for items here may help not forgetting things. A set of todo files may also work.
Check and prioritize all issues for the release, postpone some if necessary, create new issues also as necessary. An important thing is to get the documentation into an up-to-date state!
at code freeze make a release branch using release-x.x.x in mercurial IMPORTANT: bump the pypy version number in module/sys/version.py and in module/cpyext/include/patchlevel.h, notice that the branch will capture the revision number of this change for the release; some of the next updates may be done before or after branching; make sure things are ported back to the trunk and to the branch as necessary; also update the version number in pypy/doc/conf.py, and in pypy/doc/index.rst
update pypy/doc/contributor.rst (and possibly LICENSE) pypy/doc/tool/makecontributor.py generates the list of contributors
rename pypy/doc/whatsnew_head.rst to whatsnew_VERSION.rst and create a fresh whatsnew_head.rst after the release
go to pypy/tool/release and run: force-builds.py <release branch>
wait for builds to complete, make sure there are no failures
upload binaries to https://bitbucket.org/pypy/pypy/downloads
JIT: windows, linux, os/x, armhf, armel no JIT: windows, linux, os/x sandbox: linux, os/x
write release announcement pypy/doc/release-x.y(.z).txt the release announcement should contain a direct link to the download page
update pypy.org (under extradoc/pypy.org), rebuild and commit
post announcement on morepypy.blogspot.com
send announcements to pypy-dev, python-list, python-announce, python-dev ...
add a tag on the pypy/jitviewer repo that corresponds to pypy release
add a tag on the codespeed web site that corresponds to pypy release