OpenLayers is not so much released, as it escapes, leaving a bloody trail of JavaScript hackers in its wake...

Nevertheless, this is what we would do to release it, given the opportunity:

1. In preparation, branch /trunk/openlayers to /branches/openlayers/x.y, where x is the API version and y is the incremental release number.
2. Run all tests in both Firefox 1.5 and IE 6.
3. Tag the release:

    svn cp http://svn.openlayers.org/branches/openlayers/x.y http://svn.openlayers.org/tags/openlayers/release-x.y
   

4. Export it:

    svn export http://svn.openlayers.org/tags/openlayers/release-x.y OpenLayers-x.y
   

5. Build the single file version:

     cd OpenLayers-x.y/build
     ./build.sh
   

6. Install the new API code on openlayers.org

     mkdir /www/openlayers/docs/api/x.y
     cp build/OpenLayers.js /www/openlayers/docs/api/x.y
     cp -a img/ /www/openlayers/docs/api/x.y
     ln -sf x.y/OpenLayers.js /www/openlayers/docs/api
     ln -sf x.y/img /www/openlayers/docs/api
   

7. Build the tarball

     cd ../..
     tar cvfz OpenLayers-x.y.tar.gz 
   

8. Copy the tarball up to openlayers.org

    cp OpenLayers-x.y.tar.gz /www/openlayers/docs/download
   

9. Email the list and announce the release.